* ru n- m o m MOSSES AND LICHENS Nature Books With Colour Plates AMERICAN ANIMALS Witmer Stone and Wm Everitt Cram AMERICAN FOOD AND GAME FISHES David Starr Jordan and Barton W Evermann BlRD HOMES A. R Dugmore BlRD NEIGHBOURS Neltje Blanchan GAME BlRDS Neltje Blanchan MOSSES AND LICHENS Nina L. Marshall NATURE'S GARDEN Neltje Blanchan THE BUTTERFLY BOOK Dr. W. J. Holland THE FROG BOOK Mary C Dickerson THE INSECT BOOK Dr. Leland O. Howard THE MOTH BOOK Dr. W. J Holland TlIE MUSHROOM BOOK Nina L. Marshall THE REPTILE BOOK Raymond L. Ditmars THE TREE BOOK Julia E. Rogers MOSSES AND LICHENS FRONTISPIECE, COLOUR PLATE I Copyright, 1907, by DimMeday, I'asje tV Company OLD MAN'S BEARD, Usnea barbata, (L.) Fr. " The murmuring pines and the hemlocks, bearded with moss " MOSSES AND LICHENS A POPULAR GUIDE TO THE IDENTI- FICATION AND STUDY OF OUR COM- MONER MOSSES AND LICHENS,THEIR USES, AND METHODS OF PRESERVING BY NINA L. MARSHALL Author of "The Mushroom Book" SIXTEEN PLATES IN COLOUR, THIRTY-TWO IN BLACK AND WHITE, FROM PHOTOGRAPHS BY J. A. & H. C. ANDERSON; AND MANY TEXT ILLUSTRATIONS NEW YORK DOUBLEDAY, PAGE & COMPANY 1908 COPYRIGHT, 1907, BY DOUBLEDAY, PAGE & COMPANY PUBLISHED, JUNE, 1907 ALL RIGHTS RESERVED INCLUDING THAT OF TRANSLATION INTO FOREIGN LANGUAGES INCLUDING THE SCANDINAVIAN PREFACE MOSSES AND LICHENS has been written with the hope that it may meet a need often expressed, for a book with pictures which will help to identify some of the many beautiful growths which, winter and summer, in wood and open, excite the admiration and arouse the curiosity of all nature lovers. It is the result of the author's desire to know something of the dainty plants which are so lavishly employed by nature in beautifying the trails and brooks of the North woods. The more striking mosses and lichens were collected and carried about until by the kindness of one friend and another "learned in mosses," names were secured for them. No book was found which offered an easy path to the knowledge desired. In truth, no book was found which could be used at all until many months of patient labor in a botanical laboratory gave the necessary foundation. Then the author, urged on by friends who would have an easy path or none, set to work to make pen-and-ink sketches of bits of moss and details of structure. After a number had been made with some degree of success, a new plan was suggested by experience. An accurate detail was made with the aid of a microscope or was procured from a rare work, Bryologia Europe? ; and with this detail a tuft or cushion on a large scale was built up and then reduced to natural size with a camera. Later, with the success crowning persistent attempts, Mr. J. A. Anderson and Miss H. C. Anderson succeeded in photographing specimens not too small, direct from nature. The plates in the book are the measure of their success. Thanks are due to Dr. Lucien M. Underwood, of Columbia University, for his never-failing readiness to give encouragement and valuable assistance; also Mrs. E. G. Britton, who has named most of the mosses collected by the author and has been ever ready to suggest works for reference and to render assistance in other ways. Thanks also are due to Dr. Howe, of the New Mosses and Lichens York Botanical Gardens, and to Dr. Curtis, of Columbia, for assistance with certain subjects; and especially to Mr. Williams, a moss and lichen specialist of the New York Botanical Gardens, who named the lichens pictured in the book and undertook the laborious task of reading the copy before it was submitted to the publishers. The pen-and-ink drawings were made by the author direct from nature or were redrawn from the works mentioned in the "Authorities consulted." PAGE CONTENTS PART I PREFACE v I. MOSSES AND LICHENS AT HOME . 3 II. How TO KNOW THE LICHENS AND MOSSES AND WHAT THEY ARE DOING ON ROCKS AND TREES General comparison of Mosses and Lichens . 8 Poets' conception of Mosses and Lichens . . 9 Scientists' conception of Mosses and Lichens . 1 1 Soil makers 12 corroding rock 12 decomposing vegetable matter . . . 12 reclaiming marshes 15 Marsh-building on Mt. Marcy . . . . 17 Mosses which build up limestone . 17 III. LICHENS IN HISTORY Mention by early Greek philosophers . . 19 Use in dye industry .'..... 19 Use as drugs 20 Use as food 20 IV. THE ORIGIN AND NATURE OF LICHENS Spontaneous generation 22 Dual nature 22 The fungus partner 22 The alga partner 23 Experiments in artificial production of lichens . 24 How a lichen is made 24 Free fungus spore with free algal cell . . 24 Classification of algae associated . . . 25 Classification of fungi associated . . 25 Interest to the collector 26 External beauty and form .... 26 Absorbing power of water . . . . 27 vii Mosses and Lichens PAGE V. LEAFY-MOSSES Sporophytes in general 30 Sporophyte of Hairy-cap in detail . . -35 How spores escape from a spore-case ... 37 How a spore becomes a leafy-moss ... 38 How a spore-case is formed .... 39 How a Hairy-cap procures a maximum amount of light 42 How a Hairy-cap avoids too strong light . 43 Garnetophyte .... 43 Leaves in general . . .43 Leaves of Hairy-caps . . . 44 Stem ... .45 Antheridia ... . . 46 Archegonia ... ... 47 Development of a sporogonium .... 49 Veil or calyptra . . ... 50 Spore-case . . . 51 Lid or operculum . . . 51 Teeth or peristome . . 53 Teeth of Polytrichum Mosses . 55 Pedicel or seta .... -57 Asexual reproduction. Protonema from spores, rhizoids, cellular bodies, sporogonium, leaves, stems, gemmae 59 VI. THE POSITION OF HEPATICS AND MOSSES IN THE PLANT-KINGDOM AS SHOWN BY A COMPARISON OF HOMOLOGOUS PARTS ... . . . 61 VII. THE HERBARIUM How to collect Hepatics, Mosses and Lichens . 73 How to preserve Hepatics, Mosses and Lichens . 73 How to study Hepatics, Mosses and Lichens . 73 with the naked eye 73 with a lens . . . . . . 74 How to dissect Hepatics, Mosses and Lichens . 74 with a compound microscope ... 74 NOMENCLATURE .... ..... 75 ABBREVIATIONS OF AUTHORITIES . . . . ' . 75 viii Contents PART II PAGE LICHENS, GENERA AND SPECIES Genus Cetraria 79 Cetraria lacunosa 79 Cetraria hlandica 79 Genus Usnea 80 Usnea barbata 80 Usnea tricbodea 81 Genus Thelochistes . 81 Xanihoria parietina 81 Genus Parmelia . 81 Parmelia conspersa 82 pbysodes 82 saxatilis 83 perlata . 83 caperata . 83 Genus Physcia . 84 Pbyscia leucomela 84 Genus Umbilicaria ... ... 84 Umbilicaria pusiulata 84 vellea 85 Dillenii 85 Mublenbergii .... 85 Genus Peltigera ... .... 85 Peltigera canina 86 apbtbosa . 86 polydactyla 86 Genus Sticta 86 Sticta pulmonaria 87 amplissima 87 Genus Stereocaulon 88 Stereocaulon pascbale 88 " tomentosum 88 Genus Cladonia. . 88 Cladonia pyxidata 89 fimbriata 89 cristatella 89 rangijerina (typical) .... 90 cornucopioides 90 ix Mosses and Lichens PART III LIVERWORTS OR HEPATICS Ribbon-like or Thalloid Hepatics . . . 93 Marcbantia polymorpha . . . 93 Names of parts .... ... 95 Description of development ..... 95 Leafy Hepatics, Scale Mosses and Foliose Hepatics 99 Porella platypbylla . . ... 99 Names of parts . . . . 99 Genus Porella . . ..... 100 Porella platypbylla . . . . . 101 Genus Frullania . .... 102 Fmllania eboraccnsis ..... 103 Genus Ptilidium . . . .104 Ptilidium ciliare . .... 104 Genus Bazzania . . .... 150 trilobaia ...... 106 PART IV LEAFY-MOSSES Genus Sphagnum ........ 109 The method by which Peat-mosses encroach upon water to form land ..... 109 The pale tint of Peat-mosses ..... 116 The method by which Peat-mosses absorb water 1 16 The development of organs . .119 Synopsis of Genus Sphagnum . . .122 Sphagnum acutifolium ...... 123 molle . ..... 123 subsecundum ..... 124 nibellum ....... 125 cuspidatum ...... 126 squanosum ...... 128 cymbifolium ...... 128 Genus Andreasa ..... ... 130 Andrecea pelropbila . ..... 132 mpestris ....... 133 Genus Sphaerangium ....... 133 Spharangium muticum ...... 134 Genus Phascum . . . . . . . '35 Pbascum cuspidatum . .... 136 x LEAFY-MOSSES (Continued) Contents PAGE Genus Pleuridium 137 Pleuridium subulatum 138 Genus Bruchia 139 Brucbia flexuosa 139 Genus Archidium 140 Archidium Ohiense 140 Genus Astomum 141 Astomum Sullivantii . 142 Genus Gymnostomum 143 Gymnostomum calcareum 143 curvirostrum 144 Genus Weisia 145 Weisia viridula 146 Genus Trematodon 147 Trematodon ambiguum 149 longicollis 150 Genus Dicranella 1 50 Dicranella leteromalla 151 Genus Dicranum 152 Dicranum flagellare 154 scoparimn 155 Genus Fissidens 157 Fissidens adiantoides 160 Genus Leucobryum 161 Leucobryum vulgare 1 63 Genus Octoblepharum . 165 Octoblepharum albidum 165 Genus Ceratodon 166 Ceraiodon purpureum 167 " var. xanlbopous . .169 aristatus . . .169 minor 169 Genus Pottia 169 Pottia tmncaia 170 Genus Ditrichum or Leptotrichum . . . .171 Ditrichum pallidum 171 Genus Barbula I7 2 Barbula ungniculata 1 73 ccespitosa 175 xi PACE Mosses and Lichens LEAFY- MOSSES (Continued) Genus Tortula 176 Tortula princeps . . ... 1 77 " ruralis .... ... 178 Genus Grimmia . . . 178 Grimmia apocarpa . 1 79 Genus Racomitrium . . .180 Racomitrium lanuginosum . 181 Genus Hedwigia ... .182 Hedwigia ciliata . . 183 Genus Ulota .... 184 Ulota crispa ... .186 " phyllantba . .187 " Hutcbinsia . .188 Genus Orthotrichum . .188 Orthotrichum strangulatum \ 89 Genus Encalypta . 190 Encalypta ciliata . .192 Genus Georgia . . 193 Georgia pellucida . 195 geniculata . 197 Genus Tetradontium . 198 Teiradontium repandum . 1 98 Genus Schistotega . . 199 Schistotega osmundacea . . . 201 Genus Tetraplodon . . 202 Tetraplodon mnioides . . 203 Genus Splachnum . . . 204 Splachnum rubrum . . . 206 luteum . 207 Genus Physcomitrium . . . 207 Pbyscomitrium turbinatum . 208 Genus Funaria . . 209 Funaria flaricans . .210 lygrometrica . 210 Genus Bartramia . 214 Bartramia pomiformis . ..215 Genus Leptobryum ... 216 Leptobryum pyri forme 217 xii LEAFY-MOSSES (Continued) Genus Webera . Webera nut an s albicans Genus Bryum . Bryum argentcum roseum .... Genus Mnium Mnium cuspidatum .... a/fine bornum punctatum .... var. elatum Genus Aulacomnium Aulacomnium androgynum palustre . beterosticbum . POLYTRICHACE/E Key to Genera Genus Catharinea . . . Catbarinea angustata undulaia Genus Pogonatum . Pogonatum brevicaule brachypbyllum capillare urnigerum Alpinum Genus Polytrichum, with key to species Polytricbum gracile .... Obiense formosum piliferum juniperinum commune Genus Diphyscium Dipbyscium foliosum Genus Buxbaumia . Buxbaumia apbylla Genus Fontinalis Fontinalis antipyretica, var. giganlea xiii Contents PAGE . 218 . 219 . 220 . 221 . 222 . 224 . 225 . 228 . 229 . 2 3 I . 232 234 234 235 . 236 . 237 2 39 . 240 . 241 . 242 . 242 243 245 245 . 246 247 248 . 251 . 252 . 252 253 254 . 256 . 258 259 . 260 . 261 . 262 . 263 Mosses and Lichens PoLYTRICHACEyE (Continued) PAGE Genus Neckera . . . . 265 Neckera pennata . . 265 Genus Anomodon . . 266 Anomodon rostraius . 267 attenuatus . 268 " apiculatus . 269 Genus Climacium . . 271 Climacium dendroides . 272 " Americanum . . . 273 Genus Hypnum with synopsis of sub-genera . 274 Sub-genus Thuidium . . . 280 Tbuidium minuiulum . . 282 " delicaiulum . . 282 Brachythecium . . . 284 Bracbytbecium rivulare . . 285 Starkii . . 286 " NovfE-Anglice . 287 Eurhynchium . . . 289 " Eurhynchium Boscii . . . 290 " Plagiothecium . .291 " Plagiothecium Mueller ianum . 291 Amblystegium ... . 292 " Amblystegium varium . . . 293 Harpidium . 294 " Harpidium uncinatum . 295 Ctenium - 296 " Ctenium crista-castrensis . 297 Euhypnum . . . 298 Euhypnum reptile . 299 " imponens . .301 " " curvi folium . 303 Calliergon ... . 305 " Calliergon Schreberi . . . 306 " Pleurozium 307 " Pleurozium splendens . . 307 " Hylocomnium ... . 309 Hylocomnium triquetrum . . 310 AUTHORITIES CONSULTED . . 3 ! 3 INDEX . . 3 T 7 xiv PLATE COLOURED ILLUSTRATIONS I. Old Man's Beard, Usnea barbata, (L.) Fr Frontispiece FACING PAGE II. Yellow Wall-lichen, Thelochistes parietimts,(L.} Norm. 4 III. Hypnum uncinatum Hedw. . 24 Golden Cord Moss ... ... 24 Georgia pellucida, Rabenh. . .... 24 Neckera pennata, Hedw. . .... 24 Sphagnum cymbifolium, Ehrh. . . . . 24 IV. Ceratodon purpureum, Brid 42 Caiharinea angustata, Brid 42 Climadum dendroides, Web. & Mohr .... 42 Pogonatum brevicaule, Beauv . . 42 V. Parmelia eonspersa, (Ehrh.) Ach. 58 VI. A Forest Boulder ... 70 VII. Iceland Moss, Cetraria Islandica, (L.) Ach. Sticta pulmonaria, Ach Sticta amplissima, (Scop.) Mass. . The Dog Peltigera, Peltigera canina, (L.) HofYm. VIII. Reindeer Lichen and variety Reindeer Lichen, variety Alpestris 10 10 10 10 3 30 Reindeer Lichen, Cladonia rangiferina, (L.) Hoffm. . 130 Physcia leucomela, (L.) Michx 130 IX. Wood Path . . 152 X. Hairy-cap Moss, Polytrichum commune, L. . . .162 XI. Umbilicaria vellea, (L.) Nyl. 174 Rock Tripe, Umbilicaria Muhlenbergii, (Ach.) Tuckerm 174 XII. Scarlet-crested Cladonia, Cladonia cristatella, Tuckerm. 1 84 Brown-fruited Cup Cladonia, Cladonia pyxidata, (L.) Fr. 184 XIII. A Thalloid Hepatic, Marcbantia polymorpba, L. . 204 XV Mosses and Lichens PI - ATE FACING PAGE XIV. Hepatic, Dry, Frullania eboraccnsis, Gottsche . . 228 Hepatic, Porella platyphylla 228 Hepatic, Moist, Frullania eboracensis, Gottsche . 228 Hepatic, PUlidium ciliare, Nees 228 XV. Climacium dendr aides, Web. & Mohr . . . .250 Climacium Americanum, Brid 250 XVI. Hypnum curvi folium, Hedw 276 BLACK AND WHITE PLATES PLATE FACING PAGE I. The ruby-throated humming-birds know these lichens and so use them in decorating their nests as to make it difficult to distinguish them from lichen-covered knot-holes .... 34 II. The Pitted Cetraria, Cetraria lacunosa, Ach. . 80 III. Old Man's Beard, Usnea loarbaia, variety Florida 82 IV. Old Man's Beard, Usnea longissima ... 84 V. Parmelia pbysodes, (L.) Ach., variety vittata. . 86 VI. Parmelia perlata, (L.) Ach. . ... 90 VII. Spotted Lungwort, Sticta pulmonaria, (L.) Ach. . 96 VIII. Stereocaulon Pascbale, L 98 IX. The Fringed Cladonia, Cladonia fimbriata, (L.) Fr. 102 X. Bahama trilobate, L. 106 XI. Acute-leaved Peat-moss, Sphagnum acutifolium, Ehrh 124 XII. The Spread-leaved Peat-moss, Sphagnum squar- rosum, (Pers.) 128 XIII. The Broom-moss, Dicranum scoparium, Hedw. . 154 XIV. Whip-fork Moss young, Dicranum flagellare, Hedw. 170 Whip-fork Moss old, Dicranum flagellare, Hedw. 170 Ditricbum pallidum 170 Ortbotricbum 17 XV. The Curly-leaved Ulota, Ulota crispa, Mohr, and 186 Lichen, Parmelia saxatilis, (L.) Fr. . . .186 XVI. Top Moss, Pbyscomitrium turbinatum, Muell. ined. 210 The Pale Funaria, Funaria flavicans, Michx. . 210 The Water-measuring Cord-moss, Funaria bygro- metrica, Sibth 210 XVII. Webera nutans, Hedw 218 Weber a albicans, Schimp. l.c 218 XVIII. The Rose Bryum, Bryum roseum, Schreb. . . 224 XIX. Mnium punctatum, variety elatum, Bruch & Schimp 232 xvii Mosses and Lichens FACING PAGE PLATE XX. Buxbaumia apbylla, L 236 Aulacomnium beterosticbum, Bruch& Schimp. . 236 XXI. Juniper Hair-cap, Polytrichttmjuniperinum,Wi\\d. 254 XXII. Anomodon apiculatus, Bruch & Schimp. . . . 270 XXIII. The Dainty Cedar-moss, Tbuidium delicatulum, Linn 282 XXIV. Bracbytbecium rivulare, Bruch, Ms. . . . 284 XXV. Bracbytbecium Novce-Anglice, (Sull. & Lesq.) Jaeger & Sauer 288 Bracbytbecium Starkii, (Brid.) Br. & Sc. . 288 XXVI. Hypnum Boscii, Schwaegr 290 XXVII. Hypnum reptile, Michx 292 Amblystegium varium, (Hedw.) Lindb. . . 292 XXVIII. The Knight's-plume Moss, Hypnum crista- castrensis, L 298 XXIX. Hypnum imponens, Hedw 302 XXX. Hypnum Schreberi, Willd 306 XXXI. The Glittering Feather-moss, Hypnum splendens, Hedw. 308 XXXII. The Triangular Wood-reveller, Hypnum triquet- rum,L 310 PART ONE MOSSES AND LICHENS AT HOME CHAPTER I MOSSES AND LICHENS AT HOME " Children of lowly birth, Pitifully weak ; Humblest creatures of the wood To your peaceful brotherhood Sweet the promise that was given Like the dew from heaven : ' Blessed are the meek, They shall inherit the earth'; Thus are the words fulfilled: Over all the earth Mosses find a home secure. On the desolate mountain crest, Avalanche-ploughed and tempest-tilled, The sweet mosses rest; On shadowy banks of streamlets pure, Kissed by the cataracts shifting spray, For the bird's small foot a soft highway For the many and one distressed . Little sermon of peace." Willis Boyd Allen. No FREQUENTER of the woods can be unfamiliar with the more conspicuous lichens and mosses. It is with them that nature adorns her bare unsightly children. She drapes the time- worn evergreens with gray fringes (see Frontispiece) and decks ithe old tree-stumps with red or yellow corals. Soft lichens spread over the ground in the deep shade of the pine trees, while pale green or yellow rosettes creep over the fence-rails and the big rocks in the pasture lot. (See Colour Plate II.) " Far above among the mountains the silver lichen spots rest, starlike, on the stone ; and the gathering orange stain upon the edge of yonder western peak reflects the sunsets of a thousand years." Ruskin. Lichens and mosses are met with all over the world, in the cold North and in the sunny South, in the East and in the West, 3 Mosses and Lichens by the seashore and on the highest mountain peaks. They are the first growths to appear on the rocks and in the places which give no foothold to other plants. When the side of a mountain is torn away by frosts and floods, and the bared rocks, shorn of their forest trees and shrubs, are left unsightly with nothing to tempt other plants to make a home on their ledges, then the lichens come and cover the bared cliffs with delicate traceries and mantles of exquisite grays and greens. They need no soil, a polished rock will meet their need. "Meek creatures; the first inercy of the earth, veiling with hushed softness its dustless rocks ; creatures full of pity, covering with strange and tender honour the scarred disgrace of time." Ruskin. The foothold of the lichens is often so insecure that one must exclaim as he sees them, " How do you grow in such unfavour- able places ? On what do you subsist ? No soil! No water! Dry as tinder! Crumbling at any rude touch!" If the plant could answer, no doubt it would say, "There must be pioneers to open up new territory for higher plants, so from the earliest times nature has employed us to do this work. We travel swift as the wind for we travel with the wind. We are fed by the rains and the dews, the hard rocks soften at our touch and give us food." "The chapel and bridge are of stone alike, Blackish-gray and mostly wet ; Cut hemp-stalks steep in the narrow dyke, See here again, how the lichens fret And the roots of the ivy strike." Browning By the Fireside. It is true that these little plants as they lie upon the rocks, secrete an acid which dissolves the hard minerals. It is true that they have the power to condense moisture from the air, however little it may be, for they must have water as an item of food and as a medium by which mineral-salts dissolved from the rocks may enter the interior of the plant and may pass from cell to cell to those parts where they are to be worked up into plant food. The lichens are often the forerunners of rock-loving mosses as without the scanty soil prepared by their chemical action and, without the slight foothold which their debris afford, many mosses would be unable to get a start upon the forbidding rock. 4 c U u J Q z Mosses and Lichens at Home With the mosses nature first clothes naked sides of ditches and clay banks and spaces between stubble of hay and corn. These otherwise unsightly spots she covers and makes attractive with a bright green carpet. Even the hard soil along the city pavement or in the tiny city yard she covers with a velvety coat of young moss plants, although they rarely develop further than this velvet stage. " All green was vanished save of pine and yew, That still displayed their melancholy hue; Save the green holly with its berries red, And the green moss that o'er the gravel spread." Crabbe Tales of the Hall. The blackened embers of the picnic fire are hidden with Golden Cord-mosses (Colour Plate III) and the roadsides in the woods and the slopes to the lake are carpeted with sturdy Hairy-caps (Colour Plate X). The crumbling roofs of deserted cottages and the unused well-sweep and old oaken bucket are decorated with soft tufts of green. Indeed the mosses are lodged in the crevices of the stones which line the well itself and late in the winter when all the world is asleep under its blanket of soft white snow, these little mosses grow and flourish unaffected by the cold above. Nature distributes the mosses lavishly in all humid climates, regardless of altitude, cold or heat. They are found on trees living or dead, on earth or on rock, in streams and on the land. " The orange stain, which is time's finger mark on the gray wall, and the cups with scarlet edges spread for fairy banquets the soft green beds into which our feet sink, and all the loveliness which we think of when we think of mosses." Ruskin. Who has not loved the mossy banks and the little velvet cushions which cling to the plaster of the old wall (Colour Plate IV) or spring up in the crevices of the pavement, giving restful spots of green to the dreary monotony of brick and stone? Children play with mosses and lichens. Poets sing their charms. Artists endeavour to reproduce their wonderful colours traced on bark and rock. Aside from their artistic charm, mosses and lichens have other charms for all who will pause awhile to study their habits, and for all who will linger long enough to make out what the plants are doing in their humble way. They have wonderful 5 Mosses and Lichens mechanical contrivances for the physicist, curious processes of interest to the chemist, and many suggestions for the philosopher. Go into the woods and pastures after a rain. You will find a beauty and loveliness on rocks and trees and fallen logs which were not even suggested on a dry sunshiny day. The wood is in her glory at such times, and everyone who once sees her in her splendour will visit her again. " Here are cool mosses deep, And thro' the moss the ivies creep." Tennyson The Lotos Eaters: Choric song. The habit the mosses and lichens have of changing form and colour is one full of interest. The crisp gray moss cushions, which quickly turn green in the rain, must excite curiosity (Colour Plate IV). Pause awhile by a fresh green bank of Hairy- caps (Colour Plate X) wet with dew, and as the sun comes out and shines upon the little plants, watch them shrink away, changing the fresh bank into one brown and bare. Watch them again in a rain or when the evening dew is falling, to see every apparently dead brown plant revive and become green as before. The cause of the change is easily seen by one looking closely. The plant does not die when the sun shines, it simply folds the edges of its leaves together and turns them up against the stem so that their horny tips, instead of their delicate leaf surfaces, are presented to the sun. The cause of the upturning of the leaves of the Hairy-caps, the change of colour of many mosses and lichens from gray to green, the methods by which they subsist on bare and barren rocks and soils, and endure extreme and sudden changes in the dryness and humidity of the air, are all interesting questions to be answered by the microscope, together with careful observa- tions in the field. Gray or crimson Bog-mosses (see Colour Plate III), steadily working their way over swamps and ponds, preparing a foothold for larger plants, illustrate to us how the great peat-bogs of Ireland and of other parts of world were made. Whether one study the mosses and lichens for their natural beauty, for their habits, or from a botanical standpoint, they are interesting. They are true lovers of fresh air and clear running water, beautiful creatures in beautiful homes. They are 6 Mosses and Lichens at Home beautiful even when dried and pressed for the herbarium, so that one with a taste for collecting may regard the artistic as well as the useful. The wide distribution of the mosses and lichens and their power of enduring great cold renders them available for study at all times of the year. They are reported to have been found in all parts of the globe. Dr. Isaac I. Hayes who in 1854 discovered Grinnell Land, tells of finding "moss" as far north as Booth Bay in Greenland, in Latitude 76 30'. The uses to which the moss was put in their distress were varied. After improvising a hut from a crevice in the rock by filling open places with loose stones pried from the frozen ground, they made a roof of sails and thatched it a foot thick with "moss" dug with their tin dinner plates from under two feet of snow. All cracks were closed with the moss, and tapers of "moss" dipped in oil were depended upon to light their dismal quarters. The habit of using moss for filling in chinks and cracks is a common one among all pioneers, as one may see by observing the log huts in newly opened districts, for mixed with clay it forms a useful cement. This art is not known alone to man. " Within a thick and spreading hawthorn bush That overhung a molehill large and round, I heard from morn to morn a merry thrush Sing hymns of rapture, while I drank the Sound with joy and oft an unintruding guest, I watched her secret toils from day to day ; How true she warped the moss to form her nest, And modell'd it within with wood and clay." Claire The Thrush's Nest. CHAPTER II HOW TO KNOW THE LICHENS AND MOSSES --WHAT THEY ARE DOING ON ROCKS AND TREES Under the name of moss, in the popular mind, are included all small flowerless plants which grow in cushion-like tufts on stone or wood or bark. The name " moss " is made to do duty for the lichens, the mosses and their near relatives, the Hepatics, plants which differ widely in structure and appearance, as those will see who give more than a passing glance. LICHENS If a small plant, rootless, of almost any colour except bright green, grows as a dainty mat a ihal- lus flat (Colour Plate V) or ruffled (Plate II) on its support, one may suspect that it is a lichen. If in addition to this habit of growth, it bears its fruits in flattened coloured disks (Colour Plate VII) one may know it is a lichen, also if the plants branch like corals (Colour Plate XI), or hang in fringes (Colour Plate I) from the trees, and are without leaves, one may suspect that they are lichens and may be pretty sure of it if the fruits are little coloured disks or cushions on the tips of the branches. The "Florida Moss," which grows in long gray fringes from the trees in the South, is neither a lichen nor a moss, but is a true flowering plant with stamens and pistils, the old seed capsules are often found still clinging to this moss-appearing plant, in the season when it Aulacomnium Heterostichum, Moss. 8 How to Know the Lichens and Mosses Hepatic. Hepatic. Hepatic. is not in flower. It was probably to this plant Gannet referred when he wrote: "A cloister dim, where the gray moss waves, And the live-oaks lock their arms at will." TRUE MOSSES If plants are small and green, with leafy stems, and have the habit of living in such close proximity as to form Spore-case without lid. Lid. Spore-case velvety cushions, (Cera- with lid re - , movedto todon purpureum) one show teeth Spore-case with lid. Bryum argenteum. may suspect them of be- wanting. ing mosses, but if they have this habit of growth, or grow in clusters resembling tiny ferns or miniature trees and bear their spores in little cases opening by lids, one may feel confident that they are the true mosses as distinguished from hepatics. Hepatic. Spore-case split into four symmetrical valves. Ceratodon purpureum, Velvety Cushion. Mosses and Lichens HEPATICS If the plants are green, growing flat and ribbon-like or as prostrate stems with paired, veinless leaves and with fruits umbrella-like or cups which do not open by lids but split irregularly into symmetrical valves in order to permit their spores to escape, one may know them to be hepatics. The beauty which mosses lend to the surfaces upon which they live is pretty generally conceded. One has but to recall the frequent reference which our poets make to them to feel that they have always appealed to the poetic eye. Mnium affitie* Moss. " On our other side is the straight-up rock ; And a path is kept 'twixt the gorge and it, By boulder-stones where lichens mock The marks on a moth, and small ferns fit Their teeth to the polished block. These early November hours, That crimson the creeper's leaf across Like a splash of blood, intense, abrupt, O'er a shield else gold from rim to base, And lay it for show on the fairy-cupped Elf-needled mat of moss." Browning By the Fireside. Ruskin says: "To them, slow-fingered, constant-hearted, is entrusted the weaving of the dark, eternal tapestries of the hills." 10 How to Know the Lichens and Mosse Whittier in " The Bridal of Pennacook," to the query of "Why turns the bride's fond eye on him, in whose cold look is naught beside the triumph of a sullen pride ?" replies: " Ask why the graceful grape entwines The rough oak with her arm of vines ; And why the gray rock's rugged cheek The soft lips of the mosses seek : Why with wise instinct, Nature seems To harmonise her wide extremes, Linking the stronger with the weak, The haughty with the soft and meek ! " Shakespeare calls the mosses "idle": " It is dross, usurping ivy, brier, or idle moss." Comedy of Errors, Act II, Sc. 2. Scientists of to-day tell us that the rock-loving mosses and lichens are at work upon the "everlasting hills" to convert them into new soil ; that the saprophytic mosses on dead logs in the forest are at work returning to Mother Earth the materials which her tree-children took from her many years ago. They tell us that bog-mosses are reclaiming the marshes for higher plants, and that the water-loving mosses are receiving from the brooks lime-solutions which were brought up from depths below, and are laying them down in places where they are useful to man. As our knowledge of their practical value increases we shall not lose sight of their beauty, a new wonder will be added to our knowledge and many new interests to our trips "among the nodding ferns and mosses cool." Their association with aged castles and trees is so familiar to everyone that the poet has but to mention mosses and lichens to picture lonely places and peaceful decay. "Moss-muffled for- ests dim" and "the rocks where the brown lichen whitens " give to us a feeling of loneliness, while the picture of Oliver " A wretched, ragged man o'ergrown with hair " is complete when Orlando finds him sleeping on his back " under an oak, whose boughs are mossed with age." As You Like It. Act. IV, Sc. 3. Wordsworth tells us: " There is a thorn it looks so old, In truth, you'll find it hard to say I I Mosses and Lichens How it could ever have been young, It stands erect and like a stone With lichens it is overgrown." Spenser expresses another idea when he saysof the ancient oak : "But now the gray moss marred his rine ;" and Shakespeare also when he introduces Tamora, Queen of the Goths, to " A barren, detested vale . . . The trees, though summer, yet forlorn O'ercome with moss, and baleful mistletoe." Titus Andronicus, Act II, Sc. 3. Mosses and Lichens are both soil-makers. They work by two methods. The one chemical, the other mechanical. By chemical action they either construct plant tissue of gases taken directly from the air or they first free from rock or wood or earth- mould, the minerals needed and then construct them into plant tissue. By mechanical action they pry off bits of soil from hard rock, arrest dust and debris brought to them by the wind, and constantly add to the mass, such plant tissue as they themselves are continually shedding. " Upon this herbless rock a small gray lichen Did fix her home. She came with meek intent, To bless her stern and sterile place of rest ; And presently her gentle sisters followed, Some vestal white, and some in robes of brown, And some in yellow vestures, labouring all At the same work, with tiny cups held out To catch the raindrops, and with mattocks small To pierce the rock. And well did they effect Their destined purpose." One of the most important sources of the nourishment of plants is carbon dioxide (C O 2 ). It is the gas which bubbles up from "soda water" and it is the gas breathed out by animals. It is formed wherever a candle, lamp, or wood is burning or wherever vegetable or animal matter is decomposing. The gas is itself a compound of an elementary gas, oxygen (O) united with an elementary solid, carbon (C) known by the common names of charcoal and graphite. Stated in a general way, the carbon dioxide passes through the walls of the plant cells into the cell-contents and there by the leaf-green (chlorophyll) the 12 How to Know the Lichens and Mosses oxygen gas (O) is set free to return to the atmosphere, and the solid carbon (C) is worked up with water into plant foods called carbohydrates, compounds of carbon and water, of which starch, sugar, and plant tissues are examples. " A small sisterhood of plodding lichens Wrought on the rock ; the sun, the wind and rain, Helping then gladly, till each fissure filled And fit for planting, mosses came in haste And strewed small seeds (spores) among them, destined they To clothe the stern old rock with softest verdure With ferns and flowers, where yet the labouring bee May find pasture." Certain lichens carried by the winds to places unsuitable for other plants, begin their work of dissolving the inhospitable rock to obtain mineral salts which the leaf-green may, together with water, manufacture into plant food; the delicate threads of the lichen work their way in and out among the particles of rock too small to be visible to the naked eye, and as they swell with water absorbed from the atmosphere, they pry off tiny particles of rock, thus slowly but surely preparing soil for higher forms. The mosses also can take their start in life on bare and rugged rock, although not so generally as the lichens. If a tuft of Grimmia apocarpa is lifted away from the lime- stone upon which it is growing, one may see corroded depressions in the neighbourhood of the place where the stemlets of the moss colony meet, and one may see the rhizoids of the moss imbedded in loose particles of limestone which have been separated from the main rock by a dissolving fluid which the rhizoids secreted upon the rock. In this way the moss obtains mineral salts which are necessary for its growth. The solid rock is crumbled to a dust which may be blown by the wind to other localities, or which may remain on the spot and furnish soil for higher plants. In addition to the chemical action which the moss exerts in dissolving the rock, it, as well as the lichen, exerts a purely mechanical influence, for a growing rhizoid penetrates wherever the merest particle of limestone has been dissolved and by mechanical pressure separates the particles of limestone which remain. The mosses and lichens are truly efficient agents in rendering rocks available for plant life by retaining minute particles of soil 13 Mosses and Lichens but their work does not stop here, for as the older plants die and crumble and mingle with the disintegrated rock, an incredible amount of earth-mould is formed which is a favourable site for higher forms of mosses, ferns, and other spore-bearing plants. That the leafy parts above arrest to a remarkable degree the dust which pervades the atmosphere, not only along dusty road- sides and open plains, but also in remote mountain valleys, in Arctic ice fields, and in most of the elevated parts of the earth's crust, will be evident to one who detaches and examines a small tuft of Barbula, which everywhere occurs on roadside walls. He will be surprised to learn the extent to which the road dust has been lodged in the older dead parts of the plants, and he will be equally sur- prised to learn with what tenacity the dust is held. The power the older parts of the plants have of holding the dust is due to certain alterations which take place in the lifeless cell-tissue. To be con- vinced that fine dust is also carried to the more remote and elevated regions, one must examine the lichens and dark Grimmias, Andrceas and other rock mosses which grow in small cushion-like tufts on weather-beaten mountain crags, when he will find that not much less dust has been arrested by them than by the Barbula living near the dusty roadside. Old crumbled lichens, together with dust blown Andrcea rupestris . Plant with spore- thither by the wind, accumulate under the thallus, case - or leaf-like expansion of the lichen, and soon form a suitable home in which moss spores may grow. The mosses in turn add their share to the accumulation of humus preparatory to the coming of the ferns, and the ferns in turn prepare for the trees with winged seeds, the evergreens and birches, which require no very great depth of soil, sturdy pioneers of mountain forests. It is true that all green plants do a similar work, but they do not work under such primitive conditions as do the mosses and lichens. Aquatic mosses possess, perhaps to a greater degree, the power of arresting and retaining mud and fine sand hurried along by a violent rush of water. The plants of Hypnum rusciforme and How to Know the Lichens and Mosses Amblystegium rtpan'um, which cling to rocks in streams, are so conglomerated by mud and sand that they cannot be freed from it until the plants have become dried and shrivelled. Limnobium molle, which grows in the turbid waters from glaciers, has such an abundance of earthly particles adhering to it that only the green tips of the leaf-bearing stems are visible above the gray- coloured cushions imbedded in the mud. It is the dead parts alone which retain in their thick felt of interwoven filaments, the firmly divided mud and sand. That they are able to do this is due to the fact that the cell-membranes swell up and become slightly mucilaginous. This mechanical retention and storage of dust by rock-plants, and of mud by aquatic plants, is of the greatest importance in determining the development of the earth's covering of vegetation. The first settlers are crustaceous lichens, minute mosses, and algae. Larger lichens and mosses are able to gain a footing on the substratum prepared by them. " 'Tis spring-time on the eastern hills! Like torrents gush the summer rills, Through winter's moss and dry dead leaves The bladed grass revives and lives, Pushes the mouldering waste away, And glimpses to the April day." Whittier Mogg Megone, Pt. III. The dead filaments, stems, and leaves of this second genera- tion arrest dust in the air and mud in the water, and thus prepare a soft bed for the germs of a third generation, which on rocks consists of grasses, composites, pinks, and other small herbs, and in the water of pond-weeds, water-crowfoots, hornwort, and related plants. The second generation is produced in greater abundance than the first, and the third develops more luxuriantly than the second. The third may be followed by a fourth, fifth, and sixth, each successive generation crushing out and supplant- ing the one preceding it. Another marked and important change results from these small beginnings. Streams on rather flat lands are turned from their courses by the accumulation of debris made possible by the arrested sand and mud, ponds have their outlets choked so that often new outlets must be cut, and small lakes are often cut in two by a natural divide which is due to the accumulation of sand and silt bound together, first by water plants and later by shrubs and trees. 15 Mosses and Lichens The fact that at the present time the lichens and mosses are the first plants to appear on the soil, leads one to think that in ages gone by these little plants may have been the first to appear on the earth, and that they may have reigned supreme for a time in the plant world. This view is not sustained by positive tes- timony from the rocks, as there is no fossil evidence that mosses existed in Paleozoic times, nor has any certain trace of a moss been found in the coal-measures. Fossil mosses have been obtained almost entirely from tertiary and quaternary deposits. Notwithstanding that there is no fossil evidence that mosses did exist, there is no evidence that they did not exist, as their absence from the plant records written in the older formations is probably to be accounted for by reason of their insignificant size and the difficulty of their preservation. Another use the lichens and mosses subserve in the economy of Nature is illustrated by their habit of retaining great quantities of water in their spongy mass both on lofty mountain heights and in the forests of the valleys. In many parts of the world it is principally the moss-covered soil of the forests which, by collecting the rainfall, prevents the pouring down from mountains of violent and excessive torrents of water. Above the tree-line, in slight depressions on the sloping, rocky mountain sides, one may often find extensive patches of Sphagnum-moss and Reindeer-lichens which are crisp and dry on the surface, and yet retain so much water in their matted bases as to render it possible for one to obtain a supply of clear water. From areas of moss more extensive and of greater depth, tiny rills often trickle on their way to join other rills of similar origin. The sources of many a babbling brook or purling spring in the valley may be traced to the supersaturated moss-bed of a mountain forest. " Desolate ledges, frost-riven and bare, A tiny rivulet bore on their breast ; Cloud-gray mosses and lichens fair Mutely besought her to slumber and rest.'' Willis Boyd Allen. " Thou hastenest down between the hills to meet me at the road, The secret scarcely lisping of thy beautiful abode Among the pines and mosses of yonder shadowy height, Where thou dost sparkle into song, and fill the woods with light " Lucy Larcom. 16 How to Know the Lichens and Mosses MARSH BUILDING ON MOUNT MARCY Upon the open summit of Mount Marcy, 5.344 feet above sea level, there are two small marshy areas. One is a decided depression in the northeast slope; the other is on the eastern slope and nearer the summit. The water necessary to maintain the character of these marshes is probably supplied in part by rainfall, and in part by melting of snows which have accumulated in the crevices of the rocks above. The two marshes are cold botanical gardens of natural formation, unique indeed, as there is no evidence that the soil for them could have been brought from other sources, while everything suggests that the mosses and lichens at the present time growing on the bare surfaces of the rocks are active soil-makers. The boulders of the summit are variegated by the different colours of the lichens growing on their hard and almost naked surface. The rock beneath the lichens is more soft and scaly than elsewhere, and the moss tufts have the spaces between their lower stems and leaves filled with dirt and sand. The soil in most places is but a few inches deep, and largely composed of dead vegetable matter. Only plants of the most hardy nature are found here, and these are small and imperfect representations of similar plants growing at lower alti- tudes. The total number of species found on the summit is 206, of which 103 just half of the total number are dependent for their existence on the other half, the Lichens, Liverworts, and Mosses. MOSSES WHICH BUILD UP LIMESTONE In trickling springs of mountainous regions, and on the lime- stone rocks of Niagara Falls, and in other localities are found mosses which obtain part of the carbon dioxide (C O 2 ) they require by the decomposition of the bicarbonate of lime [H 2 Ca ( CO 3 ) 2 ] dissolved in the surrounding water. The mono- carbonate of lime (Ca C O 3 ), which is insoluble in ordinary water, is then precipitated in the form of incrustations upon the leaves and stems of the plants. Gymnostomum curvirostre, Trichosto- mum tophaceum, Hypnum falcatum, and others which regularly occur in streams arising from springs loaded with bicarbonate of lime [H 2 Ca (C O 3 ) 2 ] in solution become completely incrusted with lime, but go on growing at the tips as the older and lower parts imbedded in lime die off. In consequence, the bed of the stream 17 Mosses and Lichens itself becomes calcified and elevated, and, in the course of time, banks of calcareous tufa are formed, which may attain to consider- able dimensions. Banks raised in this manner are known which are not less than forty-eight feet in height. To construct them, it is estimated that mosses must have been at work on them for more than 2,000 years. 18 CHAPTER III LICHENS IN HISTORY Somewhat authentic reference to lichens is found in the writings of the Greek philosopher Theophrastus (382-287 B. C), a pupil of Aristotle. He gives us imperfect descriptions of Old Man's Beard (Usnea barbata) and Roccella tinctoria. Dioscorides, a Greek physician, and the founder of botany, who flourished in the first and second centuries, and also Gaius Plinius, a Roman naturalist (23-79), wno perished in the eruption which destroyed Pompeii, both wrote of lichens which may have been those described by Theophrnstus. It is not improbable, however, that they were speaking of Marchantia or some other liverwort. The fact that lichens had few qualities which rendered them particularly conspicuous, caused them to be largely neglected by the early botanists. They are not as a rule striking in colour, size, or form and they have no marked useful or harmful properties. The incentive which led to the early study of plants was a desire to find properties which would be of use in medicine or in the household, therefore the early herbalists gave their attention to plants with real or imaginary medicinal properties. The lichens which could yield a dye were among the first to receive attention. Roccella tinctoria is supposed to have yielded the blue and purple dye of the Old Testament (Ex. XXV 14). The dye called oricello, was certainly in use before the first century of our era. The knowledge of the dye was lost after the fall of the Roman Empire, but in 1300, Federigo, a Florentine of German parentage, accidentally rediscovered the method of preparing and using it. He is said to have achieved great success, and to have become the head of a distinguished family, the Oricellari, Roccellari, and Rucellai. From which we have orseille, the name of the dye material, and Roccella, the name of the genus of which Roccella tinctoria is a member. A blue litmus solution is produced by fermenting this lichen. It may be turned red by adding an acid and then turned blue again by adding an alkali as 19 Mosses and Lichens ammonia or limewater. For this reason it serves as a test for acid and alkaline substances. LICHENS AS DRUGS Since many lichens had a fancied resemblance to certain parts of the human body, they were supposed to be a cure for the disease of that part of the body which they resembled. Old Man's Beard (Usnea barbata, Colour Plate 1) was used to promote the growth of hair. Yellow wall lichen (Xanthoria parietina, Colour Plate II) was given for jaundice. Peltigera canina dried and finely powdered and mixed with red pepper formed an anti-hydrophobia powder ( Pulvis antilyssus) of the London Pharmacopoeia. In the history of the Royal Society it is recorded that several mad dogs belonging to the Duke of York were saved by this powder. A prescription of Dr. Mead reads: "Patient is bled and ordered to take a dose of peltigera in warm milk for four conse- cutive mornings thereafter. He must take a cold bath every morning for a month, and for two weeks subsequent, a bath three times a week." LICHENS AS FOOD " Iceland moss' ' (Cetraria Islandica, Colour Plate VII) is even now used as an article of food, as it contains a high per cent, of lichen-starch. The Spotted Lungwort (Sticta pulmonan'a, Colour Plate VII) was considered a sure cure for lung trouble and "was used in a Siberian monastery for a beer which was noted for its peculiar bitterness. The manna of the Israelites is supposed to have been a species of Lecanora (Lecanora esculenta). This lichen is plentiful in Algeria and Tartary, as well as in mountainous districts of other countries. It is its habit to grow and spread rapidly and, as it is loosely attached, it is often carried by the wind down the sides of mountains into the valley, where it is spoken of as " Rains of manna." Kirghiz Tartars eat it as "earth bread." It first forms thick-wrinkled and warted grayish-yellow crusts on the stones. Within, they are as white as parched corn. 20 Lichens in History As the plant grows older the crust is rent and loosened from the substratum, while the edges curl over until the loosened piece forms an elliptical warted body about the size of a hazel-nut. The Manna Lichen is sometimes brought down in such quantities by the rain that it accumulates to a depth of several inches, and in the Steppe region, and in the high lands of southwest Asia is used as a substitute lor corn. From the time of Dioscorides in the first century, A. D., until 1825, advance in exact knowledge of lichens was practically nothing. Between 1825 and 1868 considerable progress was made in the chemical study of lichens, the investigations still being primarily made with a view to improving the dye industry. France took the lead in improved methods of extracting dye as well as of applying it. LICHENS " Little lichen, fondly clinging In the wild wood to the tree, Covering all unseemly places, Hiding all thy tender graces, Ever dwelling in the shade, Never seeing sunny glade." R. M. E., Lichens CHAPTER IV THE ORIGIN AND NATURE OF LICHENS STRANGE opinions were entertained in regard to the origin oi lichens. The belief was general that they were spontaneously generated. In them the philosopher found the origin of plant life. "Spontaneously, inorganic stone became living plant!" Dr. Hornschuch wrote in 1819, "Algae, lichens, and mosses may develop without seed from decomposing water. The decom- position of water induced by warmth and sunlight gives rise to the common ancestral type of algae, lichens, and mosses. This ancestral type is a vegetable infusorium known as monas lens which, when acted upon by light and air, under- goes an evolutionary transformation into algae, lichens, and moss." Nees Von Esenbeck, in 1820, was wont to lead his pupils to an old castle in order to demonstrate ad oculos, how the green substance when occurring on rocks will develop into lichens. De Bary was the first author to hint at the true nature of lichens (1866). His conception of the lichen as a dual organism composed of a fungus and an alga, was upheld by the researches of Schwendener and Bornet in 1868. Further investigation seems to prove that the lichen is not an individual plant, but that it is the result of an alliance perhaps for mutual benefit between two forms of plant life, an alga and a fungus. The alga gives the green colour to the lichen and is a relative of the simple plants which make damp stone or wood- work green on the shady sides of streets and houses and trees. The fungus is a relative of the toadstools and moulds. If one look at a piece of white mouldy bread, or in the ground at the base of a toadstool, one can see a true fungus plant which is simply a network of fine white treads (hyphce) stealing their food instead of manufacturing it for themselves. They have lost their leaf-green granules, the tools with which plant-food is manufactured from air and water and mineral salts, but they have acquired the 22 The Origin and Nature of Lichens An Alga-fungus company. The cut shows a magnified portion of a lichen, Stereocaulon rantu- losum, (Sw.). (h) colourless hyphae of a fungus en- veloping, (g) filaments of a blue-green alga Scytonema. power of absorbing great quantities of water and of resisting alternate drying and wetting. The alga will perish if exposed to dry air, but when kept moist is capable of taking elements from the air and 01 manufac- turing them into plant-food by means of little granules of leaf-green it has in its cells. In the alliance the fungus is entirely dependent upon the food manufactured by the green alga and in return keeps the sun's rays from the alga and absorbs water for its work. The Alga-fungus com- pany, or lichen, is perhaps one of the earliest instances of division of labour, a little community in which one party manufactures and supplies food to the other which serves as protector. The gray-green of a lichen is then due to the fact that a bright- green plant is covered over by a translucent white plant, and the brighter green of the wet lichen is due to the fact that the wet strands of the fungus are rendered transparent by the absorbed moisture, and permit the colour of the imbedded green to be seen. A magnified portion of a dissected lichen very much resembles a tangle of fine white threads in which are scattered bits of green. The white threads of the fungus creep around in search of moisture and as a rule determine the shape the lichen is to be, while the green cells or threads of the alga follow their protecting fungus. However little moisture there may be in the surrounding air, the fungus threads absorb it for their working companion, and so the lichen can live in places too dry and parched for other plants. "Strong in loveliness, they neither blanch in heat nor pine in frost." On account of this dual nature it has been difficult to decide where to place the lichens in the plant kingdom; to decide 23 Mosses and Lichens whether they belong with the algae, with the fungi or have a place as individual plants. It is claimed that with the microscope one may often deter- mine the species of the associated fungus, as well as that of the associated alga and that this alga freed from the lichen-fungus pursues its normal mode of life and can then be identified. It is also claimed that lichens have been formed from the spores of a fungus partner allowed to germinate on free-growing algae, and that a variety of lichens have thus been developed and that the same alga will produce different kinds of lichens if associated with different fungi, and that spores of the fungus- partner have been grown on nutrient solutions and have pro- duced a fungus. One instance is known of a fungus-partner (Cora pavonia) which can lead an existence independent of the alga-partner. HOW A LICHEN IS MADE According to this theory, if a wandering fungus spore meets a group of algal cells with which it can live in harmony, a lichen- fungus-company may be founded on the spot. This lichen may grow and flourish and may from time to time send forth representatives to found new colonies. By another method, which is some- what analogous to the budding of higher plants, the partners for the new colonies arise within the parent lichen company. Certain groups of cells (So- redia) separate from the rest, each group consisting of one or more algal cells enmeshed in a dense weft of fungus hyphae. At the proper time the surface of the parent lichen ruptures, and the numerous social groups appear, giving to the old lichen that attractive hoary or frosted appearance they so often have. With the aid of the wind these easily travel, to form new companies. The fungus spores (ascospores) which enter into partnership with groups of alga cells are produced in sacs (asci, singular 24 Coccocarpia molybdia. A section of the thallus showing the green cells of the alga covered by the colourless cells of the fungus. When the lichen is damp the colourless cells are more translucent and the green cells show more and the lichen is greener than when dry. MOSSES AND LICHENS COLOUR PLATE ITI >'*"' ,- - GOLDEN-CORD MOSS. hy^rum 'tried, Silith. HYPXUM UXCIXATUM, Hedw. GEORGIA PELLUCID A, Rabenh. XECKERA PEXXATA, Hedw. A moss creeping around the tree trunk Copj-right, 1907, by Doubleday, Pag^e iS: C'>nipany SPHAGNUM CYMBIFOLIUM, Ehrh. , Crimson hog-mosses . , . illustrate how the peat-bogs . . . were made . The Origin and Nature of Lichens ascus) in organs of various shapes, knobs, or flat disks (apothe- cia), or cup and flask-like cavities (perithecia). In addition to these large spores (ascospores) of the knobs and cups there are smaller spores (conidia) produced in smaller cavi- ties scattered over the thal- lus. There is much conjee- ture as to what may be the function of these spores. In tropical countries there is found a very beautiful fanlike, greenish - yellow lichen (Cora pavonia) hav- ing a thallus marked with concentric ridges. This lichen bears its spores on the under surface on tiny clubs (basidia) instead of in sacs. The algal partner is one of the unicellular blue-green algae (Chroococ- cus) often found in muci- laginous masses in damp m A Usnea barbate, (Fr.) (A) A vertical section places. Another tropical through a strand of the Bchen. r . (B) A cross section of a strand at a point where form ( LJlCtyOncma) grOWS a radiating strand was cut in vertical section 35 delicate blue-green, felt- ($) Apex of strand, (r) cortex, (g) algae, (m) pith layer, (*) a central card, (sa) section of a radiating like plates Standing OUt branch with its central cord, (*). from the tree-branches to to which they are attached. The algal partner in this case is a blue-green, branching, and thread-like species (Scytonema) found enveloped in a mucilaginous mass in fresh water. The fungus- partner in both the Cora pa-vonia and the Dictyonema is one of the group which forms leathery crusts on twigs and tree trunks. Another lichen, Laudatea, has the same partners as the Dic- tyonema. It is a crustaceous form and in it we find the exception to the rule, that the fungus is the leading member of the lichen firm. In it the alga has the upper hand and determines the direction of the growth. One lichen (Emericella vartecolour), which resembles a tiny puff-ball, is known to be due to the confederacy of a 25 Mosses and Lichens member of the pouch-fungi group (Gasteromycetes) with an alga (Palmella). In the majority of lichens the algae are arranged in definite layers, sometimes as in the gelatinous lichens they are distri- buted through the whole thickness of the thallus. The fungus partner which, with but few exceptions, directs the growth of the lichen, determines whether it shall encrust the surface so that it cannot be removed without injury, or whether it shall form shields and ribbons lightly attached, or corals and fringes fastened at one point. Although it is impossible without microscopic examination to determine the exact relations of one lichen to another, much pleasure may be derived from an acquaintance with their external form alone. No plants are more readily preserved and none will so satisfactorily respond to one's effort to revive them. Even after they have been dry for years they will become as beau- tiful as ever if placed in a moist atmosphere. One may find them every- where and at all times of the year. Their power of absorbing moisture is tru- ly wonderful. It is stated that if living lichens which have become dry in the air, are left in a place saturated with moisture, they take up 35 per cent, of water in two days and as much as 56 per cent, in six days. Certain lichens after a long continuance of dry weather will absorb one-half their own weight of water in ten minutes and will lose it as quickly when exposed to dry air. It is an interesting experiment to put a mass of Reindeer-lichen in a glass of clear water, and note how quickly 26 Sticlima jttliginosa. (Dicks.) Nyl. A section showing (0) the upper cortex, () the under cortex, with (r) rhizoids: (m) Pith layer showing hyphae in side and end views, (g) gonidial zone, with the blue-green alga chroococcus. The Origin and Nature of Lichens it will expand into a beautiful fresh plant. One may appreciate their wonderful absorbing power by comparing the dry forest trail with a wet one. The old tree stumps are decked, as for a banquet, with branching, coral-like Cladonia, a lavish display of fairy candelabra! The red tips of Cladonia cristatella and the brown tips of Cla- donia mitrula are in rich contrast with their frosted green branches. The gray goblets of Cladonia pyxidata and Cladonia A magnified portion of Cladonia fur- cata (Huds.) Fr. (g.) The alga protococcus enveloped by colourless strands (h) of a fungus. fl.stu.S Sw/rfa-ct. Suit u> Mosses and Lichens upon this lichen, and in times when food has been scarce, even man has been glad to avail himself of it. In Sweden at one time the people made their bread from this lowly plant. In moist places, velvety green ruffles (Peltigera, Colour Plate VII) spread on the ground or on stones and stumps, the edges of the ruffles set with fruit-- disks curled in such a way as to resem- ble brown finger nails, or dogs' teeth. In the days when drugs were selected because of a fancied resemblance to the part of the body in need of cure, Pelti- gera canina was considered a cure for Section hydrophobia and received its specific ot thaiius to show aigae and hyp- name can i na because of the resemblance hae in definite layers. of its fruit-disks to a dog's teeth. When dry the surface of the ruffles is a light quaker-drab, which quickly changes to a bright green when the lichen is damp. It is on the bark of trees that one finds the richest har- vest of lichens. They are found in the greatest profusion on the north sides of the trees and for this reason serve the wood- man as a guide through the forest. Emerson in "Wood Notes" refers to this, when he says: " The moss upon the for- est bark Was pole-star when the night was dark." (Colour Plate IX) The encrusted lichens, Parmelia (Colour Plate V), and Sticta (Colour Plate VII) which grow flat on rocks and trees, cling so closeiy that they can with difficulty be separated. Their pretty gray or green mats dotted with shining brown fruits grow from the centre outward in an ever-widening circle, covering old fence 28 Ephebe Kerneri. A gelatinous lichen with the alga distributed throughout the thallus. The Origin and Nature of Lichens rails, unpainted cabins, and all other hard unsightly things which Nature wishes to render soft and beautiful. "O'er yon low wall, . . . whose rough, discordant stone Is massed to one soft gray by lichens fine The tangled blackberry, crossed and recrossed, weaves A prickly network of ensanguined leaves." J . R. Lowell An Indian Summer Reverie. Collema pulposum (nat. size). A gelatinous lichen with Nostoc as alga. The ruby-throated hummingbirds know these lichens and so use them in decorating their nests (Plate I) as to make it difficult to distinguish them from lichen-covered knot holes. The Lungwort (Sticta pulmo- naria, Colour Plate VII), so called from the resemblance of the pitted surface to the surface of a lung, does not encrust the bark on which it grows, but clings lightly to its support when moist and curls up its under white surface when dry, to protect its green surface. On the same tree with the Lungwort one often finds an hepatic (Porella platyphylla, Colour Plate XIV), with braided strands, and a moss (Neck- era pennata, Colour Plate III) creeping around the tree trunk its strands in parallel rows. On overhanging cliffs by lake or stream, or on huge rocks in the forest, one finds the oddest lichen of all, the Rock Tripe (Colour Plate XI). When wet, the velvety green shields lie flat, held by a stout cord at their centres. As the air around them becomes dry, the edges begin to curl, bringing the soot-black under surfaces to the light to form black tubes here and there over the rocks. With every change in the moisture of the air the Rock Tripe curls and uncurls, writhes, and twists; at one time presenting its gray or green surface, at another its black. This lichen is also used for food and is said to have saved the life of Sir John Franklin in the Arctic seas, when he was reduced to starvation. 29 Section of Collema pulposum to show uniform distribution of the alga throughout the whole thickness of the thallus. CHAPTER V LEAFY MOSSES " The tiny moss, whose silken verdure clothes The time-worn rock, and whose bright capsules rise, Like fairy urns, on stalks of golden sheen, Demand our admiration and our praise, As much as cedar, kissing the blue sky, Or Krubul's giant flower. God made them all, And what He deigns to make should ne'er be deemed Unworthy of our study and our love." All true mosses produce their spores in a spore-case of one shape or another which opens, with few exceptions, by a lid. The spore- case may be situated at the summit of the stem of the moss-plant or on one side of the stem. It may or may not be supported upon a pedicel (seta). Many species of moss have two rows of teeth about the rim of the spore-case, while some have one row and some have none. The Spore -case Plant with closed opening with- spore-case. out a lid. Andrea rupestris. An exception to the rule that a moss spore-case opens by a lid. Potlia trun- cata; spore- case opening by a lid. Plant with spore-case im- Spore-case open mersed by the and spores falling. leaves. Archidium Ohiense. An excep- tion to the rule that a spore-case opens by a lid. Leafy Mosses Spore -case with lid re- moved to show Portion of single row of peristome. teeth. Neckera pennata. Gymnostomum cal- careum. Spore-case without teeth. Hypnum uncinatum. Por- tion of peristome to show cilia and teeth of the inner membrane and one tooth of outer membrane with annulus at the base. teeth may vary greatly in shape and num- ber; as a rule, there are four, sixteen, thirty- two, or sixty-four. The spore-case when immature is often covered by a cap or veil (calyptra). The veils vary in shape and in size, sometimes persisting a long time, sometimes falling away in the early stages. All leafy mosses have leaves which may vary in size, in shape, in Funaria hygrometrica. Spore- cases borne on pedicels grow- ing at the summit of stem. Thuidium delicatulum Spore - case sho wi ng two rows of teeth. Brachythecium rivulare. Spore-case borne on a pedicel growing from the side of the stem. 31 Mosses and Lichens texture, in colour, and in the nature of the margin, this being sometimes entire, and sometimes toothed, sometimes with a thickened margin or with one made up of cells very different from those within. The species of mosses are based on the characters of the plant, the spore-case, the pedicel, and the leaves, together with their habit of growth. Everything about the moss-plants indicates that their purpose in living is to reproduce their kind. Each part is designed and perfected with this end in view. In the struggle for existence they have come to adapt themselves to the most varied condi- tions, but a certain amount of water is as necessary to them as to all other forms of life. Without water the male cells can never reach the egg-cells and the leaf-green (chlorophyll) cannot manu- facture plant food. It is true that there are species which have ceased to attempt the formation of spores in localities where the rainy season is never long enough to permit their reaching maturity. In such species the plants become very dry, the leaves Funaria hy- grometrica. With an immature spore-case cov- ered by its veil. Polytrichum brachyphyllum. Spore-case with hairy veil Fissidens adi- antoides. Spore- case with one row of teeth. Dicranclia heteromalla. Spore-case with and without a veil. 52 \ Polylrich- um pilifer- um. Leaf with apex prolonged into an awn. Ge orgia geniculata. Spore -case with four teeth. Leafy Mosses and branches break off and are blown hither and thither by the wind, each piece being capable of growing into a new plant, if it has moisture long enough to permit it to get well started. It can then endure long periods of drought and can avail itself of small quantities of moisture which may be condensed from the air. It must be remembered that normally all plant food is manu- factured by the green colouring matter in the leaves and stems of plants, and that these little agents can work only in the light. The light must not be too weak, or the leaf-green becomes yellow and cannot work; again the light must not be too strong or the leaf-green is destroyed and the water in the plant is too rapidly evaporated, with the result that the plant dies. In order that moss plants may avail themselves of small quantities of water and may Polylrichum commune. Summit of spore- case showing membrane surrounded with sixty-four teeth. Apex of leaf to show entire margin. Catharinea undulata. Tip of spore-case with thirty-two teeth at- tached by their tips to a membrane. Octoblepharum albidum. Spore- case with eight teeth. Spore-case. Part of peristome. Ulota HiilchinsuB. Aulacomnium heterostichum. Leaf apex to show serrate margin. 33 Mosses and Lichens withstand the fierce heat of the sun, they have various interesting contrivances for folding their leaves so as to retain what moisture they have absorbed, and they have methods of trans- ferring their delicate leaf-green from one part of the plant, too much exposed to the sun, to a part less exposed, or of surrounding the leaf-green-bearing cells Stem with leaves. Portion of leaf to show- marginal cells different from body cells. Mnium punctatiim. Mnium cuspidatttm. Stem with leaves. Pogonatitm Alpinum. Apex prolonged into an awn. Margin serrate Surface covered with delicate cells. in a wall of large colourless cells. This arrange- ment accounts for the fact that some mosses, as the peat-mosses (Sphagnum, Plate XI), white- mosses (Leucobryum, Colour Plate IV), and others appear light gray when dry and green when wet. The luminous moss has given up the struggle for a place in the outer world and has retreated to caves where but a few rays of light enter. It has adapted itself to the semi- darkness by devising a method where- by it can con- verge the sev- eral feeble rays which fall upon it so that they form one beam oio-pUss Cell. Sphagnum cymbifolium. Surface view of leaf- Bryum argenleum- Leat wivh open cell - structure MOSSES AND LICHENS PLATE 1 . . . The ruby-throated hummingbirds know these lichens and so use them in decorating their nesis as to make it difficult to distinguish them from lichen-covered knot-holes. . . . Leafy Mosses sufficiently strong to permit their leaf-green to manufacture plant food. THE HAIRY-CAP MOSSES Among the best subjects for a beginner are the Hairy-caps, the most common mosses, which every- one who frequents the woods will find bordering trails and wood-roads, or covering the ground in -ilade\ Ctlls con-> ltu.-f- ' Pogonatum ur- nigerum. Leaf open to expose the delicate surface. Cross-section of closed leaf. .CtllS cent OLLVX-; CH.T or w/ixttr. Leucobryum vulgare. Cross-section of open leaf. Polytrichwn almost all open places. They are so large that with a hand-glass many of the principal parts may be made out and will thus serve as a foundation for a study of other mosses. FRUITING PORTION (SPOROPHYTE). The most striking part of the plant (Gametophyte) is the fruiting portion (sporopliyte) with its parts. The spore-case is a thin-walled cylindrical box with four or six sharp edges running lengthwise. The spore-case is borne on a flexible pedicel (seta), the sporf- two together resembling a apophysts tiny Turkish pipe. In cer- tain stages of this moss the spore-case is entirely covered with a conical light -brown, hairy Leaf closed to jj cover the del- , , surface, veil fringed about the Polylrichiim jumperinum. Mosses and Lichens base. When this veil falls, the case is tightly shut by a round lid, resembling in some species a tiny Tam-o-Shanter, and in others a tiny dunce-cap. The lid has a point in the centre and its edges fit closely about the rim of the spore-case. When the lid is thrown off, sixty-four blunt teeth are seen to border the rim of the case. They are bent inward, and bear at their extremities a thin mem- branous disk (epiphragm) which now closes the case. .Veil Pedicel Leaves leaves Polytrichvm P i'lfcnitn . Moss Gametophyte. Spore-case without veil and with a Spore-case short -pointed with veil - lid. Polytrichum juniperinwn. Polytrichum gracile. Spore- c a s e with long-pointed lid. Polytrichum commune. Summit of spore-case with sixty-four teeth surrounding a membrane. Within the spore-case are myriads of green, dust-like spores, which, when scattered 36 Leafy Mosses by the wind, will grow into new plants, if they fall in favourable places. HOW THE SPORES ESCAPE FROM THE SPORE-CASE When the weather is damp, although the spores are ripe, the teeth of the Poly- trichum mosses hold the membranous disk so that the spores cannot escape. When the weather is dry the teeth are so modified as to make a ring of holes be- tween the teeth and the edge of the disk, through which the spores may pass. There are mosses with their teeth trian- gular in shape. These have the bases of the triangles fastened at the rim and the points Teeth. Tetraplodon mnioides. Spore-case with eight pairs of teeth turned back. Leucobryum vulgare. Portion of single peristome showing four teeth split half way to the base. Polylrichum juni- perinum. An o 1 d sporophyte with lid removed. Georgia pellucida. Top of spore -case with four teeth. meeting at the centre. In some species the teeth simply arch up, remaining fastened at the points, and let the pores escape, wh in other species they turn back like the ray flowers of a daisy. Some species have at the base of the teeth a single or double row of short bead-like cells (annulus) which swell up at the proper time to push off the spore-case lid. 37 Teefh Funaria hygrometrica. Summit or spore-case. Mosses and Lichens When the spores of the Hairy-cap are mature, the pedicel bends to bring the spore-case into a horizontal position, and the sides of the spore-case wrinkle up, and by so doing oust the spores. HOW A SPORE BECOMES A LEAFY -MOSS PLANT The spores which the wind carries from the spore-case to favourable places germinate. The spore first swells and sends forth a delicate tube which divides into a net-work of cells (protonema). Some cells (rhi^oids) of the pro- tonema contain leaf-green (chlorophyll) and extend over earth or wood or stone as a fine green web. Upon this green web little bud-like structures appear which develop into leafy Spores. Widely branching protonema. w. Rhizoid of the moss-plant starting at K. h. A main filament of protonema from which branch- ing protonema / has grown. Funaria Inygromelrica Spore germinating. w. Rhizoid; s. Outside wall of spore; v. Vacuole; p. Pro- tomena. moss-shoots. The leafy structure is the part one ordinarily sees and knows as "moss." As a rule, when the Hairy-caps and other mosses are well grown, the protonema disappears. In a few species, as in the Beard Moss (Pogonatum brevicaule), it persists, being visible as a soft green covering on the ground, with small plants on its surface and conspicuous spore-cases erect upon the plants. 38 Leafy Mosses HOW A SPORE-CASE IS FORMED Upon the leafy part which is known as the moss-plant there soon appear little organs which together are to produce the sporophyte, spore-case, pedicel and foot. PedUA cluster. Fertile branch. c(.u.sti,T, Plant stripped of leaves to show male <5 and female 9 branches. Tetraplodon mnioidcs. Monoicous inflorescence. Funaria hygromclrica. Monoicous inflorescence. One organ contains an egg-cell and is known as the arche- gonium; the other organ contains the fertilising cells (sperm- cells) and is known as the antheridium. The archegonia and antheridia of the Hairy-caps are on 39 Mosses and Lichens different plants (dioicous, two households). This m plan is common to many species of mosses, while other species have the antheridia and archegonia on the same plant (monoicous, one household). duster . second . ' * " ) ' " lal cluster- jtrst ^jtar. ^.'\_ .^L- Sperm cell. Terminal male *-- Female plant. Male plant. flower-cluster. Anlheridtiim bursting and sending Polytrichum. Dioicous inflorescence. forth sperm cells. (See page 46.) & Phascum cuspidatum. Paroicous inflores- cence. Vertical section through stem to show (an) male and (ar) female flowers side by side on the same plant. (i>) Leaf blades, (p) Paraphyses. Trematodon ambiguttm. Examples of autoicous inflorescence. Two male clusters and one female cluster. Leafy Mosses The sperm-cells which develop in the antheridia are tailed and swim in water to an archegonium which contains an egg-cell. The sperm-cells pass down the necks of the archegonia, unite with the egg-cells, and after Vein Stfifn Cttt leaf Bryum binum. Stem cut vertically. Summit of a stem with two perfect sporogonia and five withered antheri- dia. One sporogo- nium i s entirely within the arche- gonium wall . the as a calyptra. Funaria hygromelrica. Moss stem cut vertically to show (a) archegonia alone, (6) leaf blades. the union, each egg-cell be- other is raising the gins to divide, forming new archegonium wail cells until a spor- ogonium is com- pleted. As the spor- ogonium, still within the archegonium wall, grows up- ward, the wall of the archego- nium is torn away at the Phascum ciispidatum. Stem cut ver- baSC and IS tically to show (ar) archegonia on one Carried UP as branch and (an) antheridia nearby on another branch' (p) paraphyses and a veil on the (6) i ea f blades. Mosses and Lichens growing sporogonium, thus the veil of the spore-case is the old archegonium wall. HOW A HAIRY-CAP PROCURES A MAXIMUM AMOUNT OF LIGHT The leaves of a Polytriclmm have many points of interest. It is a recognised law in nature that the position of the leaves of a tree or plant is such as to admit the greatest amount of light and air possible to the great- est number of leaves. Since it is the habit of these mosses to grow perpendicularly with little or no branching and to have the leaves long and slender, the leaves are so placed on the stem as to form a spiral of leaves, every eighth leaf lying directly above the first one counted. If a line be started atone leaf, and wound about the stem joining all eight the apex. leaves, it will be found that it has coiled three times about the stem. The leaves joined form "one story." If a plant with several stories of eight leaves each has straight perpendicular lines drawn joining leaves which c l <* P eum. Cross section Anomodon apicu- lattis. Leaf with vein extending to lie one directly above another, it will be found that the dis- of leaf showing blade one cell thick, and vein Pogonatum Alpinum. Upper view showing Vansparent base tanCC between each line is 3/9, Of several cells thick. and lamella cover- r r ^i ing the surface ex- the circumference of the stem. cepting along the The fraction which represents the horizontal distance will always have for a numerator the number of spirals in a story and will always have for the denomi- nator the number of leaves in a story. In some Polytriclmm mosses every thirteenth leaf is directly over the first one counted, so that it would require a spiral of five coils to connect all thirteen and would require the circumference to be divided by thirteen perpendicular lines, each line fV f the circumference 42 (i H , o ty: e G S o 1-1 u Leafy Mosses from the next line. If the two fractions are reduced to the same denominators y T and f\ n T and compared, it will be seen that the leaves were but little more crowded. The extra crowding is compensated for by the greater distance between two succeeding leaves in the same line and by the fact that the leaves in the second instance are narrower than the first. HOW A HAIRY-CAP AVOIDS TOO STRONG LIGHT The devices for avoiding the extreme heat of the sun are per- haps still more wonderful than those for obtaining a sufficient amount. It is a fact that in the leaves of the Hairy-caps only the upper surface of the leaves is so constructed as to be injured by too dry heat. The cell walls of the lower surfaces are on the contrary thick and impervious to water, so that they cannot give Bryum argenteum. Leaf with open cell - structure and midvein extending only part way to the apex. Calharinea undulata. Cross section of leaf to show the leaf- blade one cell thick, and the lamellae rising from a thickened vein. Dicramtm flagellare. Part of leaf to show open cell- structure of base. Solid vein on the right of cut. up moisture to the air when it is dry, a character which insures against loss by evaporation, for when the air is dry the mosses simply turn the awn-pointed leaves upwards with the points and the impervious under-surfaces to the sun and the delicate cells toward the stem. VEGETATIVE PART (Gametophyte) The structure of the leafy-mosses is mostly very simple. The leaves are generally but one cell thick from surface to surface, except along a line from apex to base where they form a mid- vein (costa). 43 Mosses and Lichens The leaves have no epidermis and no breathing pores as do the leaves of higher plants. LEAVES OF POLYTRICHUM The leaves of a Polytricbum represent about the highest stage in the development of mosses. The mid-vein is broad, and only at the extreme margins is the leaf-blade one-layered. The central tissue of the mid-ribs of the leaves continue so as to unite with the central axis of the stem in a manner quite analogous to that found in stems of higher plants. A cross section of a leaf shows that the marginal cells and a line of cells running through the central part are comparatively thin-walled and are Catharinea angustata. Cross section of leaf to show the thin blade and two lamellae rising from the vein. Pogonatum Al- pinum. Upper face of leaf to show deli- cate lamellae. Catharinea ttndulata. Upper surface of the apex of a leaf showing lamellae with thin leaf -blade on either side. empty water-conducting cells similar to the wood-ducts (trachea?) of a fibro-vascular bundle in a higher plant. The next layer is composed of similar but smaller cells containing starch. The rest are thick- walled cells (sderenchyma). The outer cells contain more or less leaf-green (chlorophyll}. When breathing pores occur they are on the spore-case walls. The cells of the upper surfaces, have their walls exceedingly delicate, so that they can absorb gases and permit gases or water to leave them. The thin blades (lamella) are undoubtedly the 44 Leafy Mosses result of an effort on the part of the plant to increase to the high- est degree its absorbing surface without widening the leaf-blade itself. By directing the growth of the delicate cells upward in thin blades, this end is accomplished. a. Polytrichum. Cross section of a portion of a leaf to show: (a) lamellae, (s) sclerenchyma. Thickened cells of vein. The leaf -blade one cell thick shows on the left. Polytrichum slnctum. Cross section of leaf through the midvein to show bead-like lamellae on the upper surface and thick-walled cells on the under-surface. THE STEM The stems of most mosses are simple in structure, they have no vascular bundles for strengthening the stem and for the pur- pose of carrying liquids from one part to another. The cells of one part differ but little from the cells of another part ; those on the exterior may have thicker walls so as to form a firmer rind- layer, and those of the interior may be elongated and serve for the storage and transmission of albumen and hydrocarbons. The stem of the Hairy-cap is perhaps the most highly devel- oped of all moss stems. A cross section shows a central portion of thick-walled cells 45 Mosses and Lichens with here and there cells whose walls have remained thin and yellowish. Immediately without the central portion is a zone of several layers of thin-walled narrow cells, bounded dendroides. Mnium undidatum. Cross j,,/ , -,IVM,,Y,/,H jtnftirira Pr-nc<: (^lwlac^um dendrotdes. Aulacommum pabistre. Lross section of stem to show cell nf rpntral mrt of <;tem CrOSS Section OI central _ structure without fibro-vascu- lar bundles. part of stem. on the outside by from one to three layers of cells with thin, mostly dark-brown, walls. These as well as the cells lying immediately within are char- acterised by the starch contained in them as are the narrow cells of the leaf-traces. The "roots" are very simple in structure, being either hair-like tubes or simply chains of cells. To dis- tinguish them from the roots of higher commune. plants they are called rhizoids. Cross section of stem. ANTHERIDIA Antheridia, or the male organs of the Bryophytes, are spheri- cal, oval, or club-shaped bodies, with long or short stalks. They consist of an outer wall of a uniform layer of cells, and an interior tissue formed of numerous small cells, in each one of which a sperm-cell has its origin. (See diagram on page 40). The sperm-cell is a spirally coiled filament, thickened at the rear and pointed at the forward end with two long fine cilia projecting from the point. When mature, the antheridia walls rupture, and the sperm- cells, in virtue of their coils, spring from the antheridia and by means of their cilia swim in water to the archegonia. 46 Leafy Mosses ARCHEGONIA An archegonium is produced by a multiplication of cells which form a flask-shaped body. The lower or swollen part of the flask contains an egg-cell (ovum) and the upper portion is drawn out to form the vein neck which in t he early stages . ri , , ...f is filled with a layer of cells. Later the chain of cells becomes a mucilaginous jelly, w h swelling with water, bursts openthelidofthe neck, and lying on the summit arrests the sperm cells which pass that way in the water, and directs their course down the neck of the flask to the egg-cell (ovum) with which they are to blend. >-. htcx ....Wall. Bryum binum. Vertical section of stem. Sections of archegonia. Sphagnum cuspidatum. 47 Mosses and Lichens The archegonia and antheridia are developed among the leaves of the moss-plant. As has been stated before, they may be on separate plants (dioicous, of two households), or they may .Pedicel ciu.8tcr. Climacium dendroides. Sporogo- nium. (a) Spore-case with lid. (b) Columella attached to lid. (c) Spore-case with lid lifted to show teeth, (d) Spore-case with veil. (See page 49.) Funaria hygr ometrica . Autoicous inflorescence. both be separated on different parts of one plant (autoicous), or side by side on the same plant (paroicous) or on the same part of the same plant (synoicous) Monoicous one household is a general term including the last three forms. 48 Leafy Mossea THE DEVELOPMENT OF A SPORE-CASE (Sporogonium) After the union of the sperm-cell of the antheridia, with the egg-cell of the archegonium, a division of the egg-cell takes place, Vertical section through male flower-cluster, (a) Young Vertical section through antheridium. (b) Mature antheridium. (c) Paraph ysis. female flower-cluster, (a) Ar- (d) Leaf -vein, (e) Leaf -blade. chegonium. (b) Leaf-blade. Funaria hygrometrica. Dioicous inflorescence. (See page 48). which brings about a multiplication of cells, the ultimate result of which is a mass of tissue called a sporogonium, which is the Sport- case. a maul us ..Tee tli Sphasrangium muiicum. Sporogonium with wall partly removed to show colum- ella with spores attached. Funaria hygrometrica. Summit of sporo- gonium to show the annulus rolling back from the teeth. fruit of the moss made up of the lid, spore-case, teeth, annulus, spores, and columella. (See diagrams on pages 48 and 53.) 49 Mosses and Lichens CALYPTRA The calyptra or veil is the dry remains of the outer wall of the archegonium in which first the egg-cell and then the embryo moss-plant were developed, for as the em- bryo within enlarges, the wall of the archegonium sooner Funaria hygrometrica. Young sporogonium still covered with its veil. Encalypta ciliata. Old sporogonium with fringed and transparent veil. Two developing sporogonia with five shrivelled arche- gonia at their base. The figure on the left shows the archegonium wall severed from its base thus disclosing the pedicel of the spore-case within. Pogonatum brachy- phylluin. Spore-case with hairy veil. or later ruptures near the base, and is carried up by the grow- ing spore-case. This severed archegonium wall may be thin and smooth and often split up one side, or it may be as in the Hairy-caps rough with hairs, caused by the stretching and ultimate rupturing of the fibres which composed the tissue of the walls. 50 Tetradontium repanditm. Spore- case with conical veil. Leafy Mosses SPORE-CASE In the early stages of a developing spore-case the cells may be distinguished as forming two groups, first an outer wall con- sisting of a number of layers of cells and second an inner mass of cells; the outer wall is separated from the inner mass by a Veil split up one side. Spore-case borne on a short pedicel, lid wanting. Astomum Sullivantii. (See page 50). Spore-case with veil. space filled with air. The centre portion of the inner mass will become the columella and the enclosing stratum of cells (arche- sporium beginning of spores), will be the " mother-cells " of the spores. Just outside the mother-cells between them and the air-space will be a layer of cells (the endothecium). Fiit y-Tt I tl . Tu.iu.r-t tts.tb... Zo-n i of tells (_ future unntt/u oill bt COTVIC disttni- d UJltrl Uiato ani f-r ee tkt. ce-Us a-tovtto OT-JXX o. Hi.. ports. cells. _0uttr iuowl\. .-.Inner >nass Funaria hygromelrica. Portion of a vertical section through a young sporogonium. Sphagnum acutifoltum. Ehrh. Vertical section through an early stage of a sporogonium. THE LID OR OPERCULUM The upper part of the spore-case is in the leaf-bearing mosses usually thrown off as a lid (operculum). In order that the upper portion of the spore-case may be separated from the lower, either 51 Mosses and Lichens one of two things happens: The walls of a zone of cells of the spore-case wall, in the exterior layer, separates from the adjoining walls when the spore-case is mature, or a zone of cells consisting of one or more rows has the cell-walls modified so that when they are distended by absorbed moisture, the zone of cells is dis- placed as a ring or annulus and so frees the outer layer of cells in the upper part of the spore-case to form a lid. Lid. Spore-case with lid. Mnium affitte. Lid. Spore-case without lid, Polytrichum commune. Tooth. Spore-case with lid. Spore-case without lid. Bryum argenteum. Lid. Trematodon ambiguum. Vertical section of a single peristome, (See page 53). Lid Ulotacrispa, Double row of teeth. (See page 53). Spore-case with lid. Spore-case without lid. Polytrichum sexangulare. Leafy Mosses TEETH OR PERISTOME When the lid falls, as a rule, one or two rows of teeth are discovered. They are the remains of the cell-walls lying just within the layer which separated as a lid. (See diagrams on page 52.) If the outer walls of this layer of cells become thickened and split from the summit downward, but one row of teeth will be formed; if the inner walls as well, become thickened, and only __ ___ 6 T V 6 vcra, bellows, and ol8, like, and refers to the inflated character of the lobes. NOTE : The illustration shows a variety (vittata) with the thallus more narrowly dissected than in the species. 82 MOSSES AND LICHENS PLATE III OLD MAN'S BEARD, Usnea barbata, variety Florida Lichens, Genera and Species Parmelia saxatilis, (L.) Fr. See Plate XV. Habit and habitat. On rocks. Vegetative organs (thallus). Greenish or ashen-gray above (sometimes reddish) somewhat ornamented with a fine network and with shallow depressions; black beneath with dense hairs (rhiqoids) reaching the margin, much cleft with narrow lobes, with margins wavy and bordered with a fine white beading (soredia). Fruiting organs (apothegm). Chestnut border (thalline ex- ciple), rather thick, somewhat evenly notched. Spores. Simple, ellipsoid, colourless. Name. The specific name saxatilis, the Latin for "rock," refers to the habitat. Parmelia perlata, (L. ) Ach. See Plate VI. Habit and habitat. The lichen is found on both rocks and trees. Vegetative organs (thallus'). Greenish-yellow, gray green, slate colour and even light brown above; black beneath with a reddish-brown border which rolls up so as to bring the brown lobes in rich contrast to the surface colours. The lobes have no fine hairs on their margins and are frequently covered with a white powder (soredia). Fruiting organs (apothecia). Large, greenish-brown, entire margins which split down to the centre when the disk is mature. Name. The specific name perlata is the Latin for "widely spread." The Wrinkled Parmelia, Parmelia caperata, (L.) Ach. Habit and habitat. Grows on trees and rocks to form light pea-green, wrinkled and wavy mats. Vegetative organs (thallus). -- Leaf-like, appressed, hori- zontal, cartilaginous; lobes usually broad and rounded with entire margins; the upper surface usually covered with a very light green powder (soredia) ; the under surface, black with a reddish-brown margin and scattered thread-like bodies (fibrils). Fruiting organs (apothecia). Cup-shaped, with wavy margins often grainy (sorediferous). Spores. Ellipsoid. Name. The specific name caperata, the Latin for "wrinkled," describes the habit of growth. 83 Mosses and Lichens Genus PHYSCIA, Fries. The vegetative portion (thallus) of the Genus Physcia is leaf like, star-like, or sometimes with narrowly linear divisions, beneath it has usual fibres of varying length; the generic name is from the Greek (frvo-fcrj, a blister, evidently referring to the inflated appearance of the thallus in some species. The fruiting portion (apothecid) are shield-shaped, with the surface often covered with a whitish powder: The spores are elliptical, brown, two-celled in our species. Physcia leucomela, (L.) Michx. See Colour Plate VIII. Habit and habitat. On trees, most common southward. Vegetative organs (thallus). --Ascendant and elongated, mostly smooth, often narrowly linear, the densely entangled lobes irregularly divided; beneath white, the margins beset with strong, branched blackish fibrils. Fruiting organs (apothecia). Medium-sized, on short pedi- cels, the disk white, powdery, the border lobed; the spores are bilocular. Name. From the Greek Xeu/eo?, white, and //.eXa?, black, referring to the strong contrast between fibrils and surface. Genus UMBILICARIA, Hoffm. Thallus horizontal, leaf-like (foliaceous), scarcely divided, leathery; either smooth or fibrillose beneath, attached to its support by a single point. Fruits (apothecia) black, round, convex or sometimes irregular in outline. Spores somewhat coloured, ellipsoid, either without cross- walls or with both horizontal and vertical walls. The generic name is from the Latin umbilicus, a navel, referring to the single point at which the thallus is attached to its support. The Blistered Umbilicaria, Umbilicaria pustulata, (L.) Hoffm. Habit and habitat. On rocks in dry localities. Vegetative organs (thallus}. Horizontal and leaf-like, carti- laginous; ash-coloured above, whitish toward the centre, pale brownish or ash- coloured below; smooth on both surfaces, 84 MOSSES AND LICHENS PLATE IV OLD MAN'S BEARD, Usnea. longissima Used to promote the growth of hair. A member of the genus Ramalina is seen on the lower end of the twig, and a member of the genus Parmelia is seen on the upper end Lichens, Genera and Species often covered with a white powder (pruinose), with numerous pustular prolusions above and corresponding indentations below. Fruiting organs (apothecia). Somewhat shield-like. Name. The specific name pustulata is the Latin for "blistered" and refers to the protusions on the thallus. Rock Tripe, Umbilicaria vellea, (L.) Nyl. See Colour Plate XI. Habit and habitat. On rocks in high mountains. Vegetative organs (thallus}. Large, one-leaved, leathery and somewhat smooth, ash-coloured with a bloom above; brownish to black, and hairy, below. Fruiting organs (apothecia} Small, appressed, orbicular and plaited, becoming convex. Name. From the Latin vellus, fleece, referring to the hairy nature of the under surface. Umbilicaria Dillenii, Tuckerm. Habit and habitat. On rocks. Vegetative organs (thallus). Leaf-like, leathery, the largest species known; brownish-green above, smooth and even; in- tensely black below with crowded, short fibrils, attached only at one point. Fruiting organs (apothecia}. Orbicular, convex, attached only at the centre, the disk ridged concentrically. Name. Named in honour of the great botanist Dillenius. Umbilicaria Muhlenbergii, (Ach.) Tuckerm. See Colour Plate XI. Habit and habitat. On rocks. Vegetative organs (thallus). Large, leathery to rigid, irregu- larly pitted; olive-brown above, darker below. Fruiting organs (apothecia). Oblong and appressed, passing into irregular, often star-like plaited clusters without a common margin. Name. The specific name was given in honour of a Henry H. Muhlenberg. Genus PELTIGERA, (Willd.) Fee. The Crescent-shield Lichen. The vegetative portion (thallus} of the Genus Peltigera is leafy and often large; it is veiny and rough, hairy beneath; the algal layer is blue-green, excepting in two species (venosa and aphthosa). 85 Mosses and Lichens The generic name Peltigera from the Latin pelta, a shield, and gerere, to carry, refers to the fruits which are shield-shaped with a more or less scalloped border; they are borne close to the upper surface of the thallus, usually some distance back from the margin but occasionally on the margin. The spores are long and narrow, four- to many-celled, at length colourless. It is a small genus of mostly cooler regions. The Dog Peltigera, Peltigera canina, (L.) Hoffm. See Colour Plate VII. Habit and habitat. This lichen grows in extensive patches on logs or on the ground. Vegetative organ (thallus). Large greenish-gray, ashy, or brownish: membranaceous, round-lobed; furrowed and downy on the upper surface: whitish beneath with light-coloured veins and hairs, sometimes becoming dark. Fruiting disks (apothecid). Reddish-brown; of large size; rounded, becoming semi-revolute and vertical. Supposed to resemble dogs' teeth and for this reason, on the supposition that "Like cures like," used as a remedy for hydrophobia. Name. The specific name canina from the Latin canis, a dog. Spores. Somewhat needle-shaped; four- to eight-celled. Peltigera aphthosa, (L.) Hoffm. and P. polydactyla, (Neck.) Hoffm., are quite similar in general appearance to P. canina, (L.) Hoffm. P. aphthosa however, has the thallus smooth above, more or less sprinkled over with brown warts, and contains green algae, not blue-green as in the two following species. P. poly- dactyla differs from canina in being smooth above and nearly naked beneath and conspicuously reticulated with brown veins. Genus STICTA (Schreb.) Fr. The thallus is leaf-like, variously lobed but with the lobes usually wide, rounded, or elongated. The under surface is some- times smooth but is commonly covered with short, soft hairs (villous}, and dotted with little cups or rounded heaps (cyphels). A cross-section of this lichen shows that the irregular, coloured zone (gonimous layer) is composed of either green cells (gonidia) or bluish-green cells (gonimid). The fruiting organs (apothecid) are shield-like (scutellcefonri) , elevated, and near the margin of the thallus. 86 MOSSES AND LICHENS PLATE V PARMELIA PHYSODES, (L.) Ach., variety vitlata Lightly attached to its host reddish-brown fruiting disks, large and shield-shaped with entire margins Lichens, Genera and Species The generic name Sticta from the Greek CTTY/CTO?, dappled, refers to the strikingly spotted appearance of some species. The spores are spindle or needle-shaped with 2 to 4 cross- walls; they are reddish or colourless; they vary but slightly in the different species. Sticta pulmonaria (L.), )f Ach. See Colour Plate VII;*^ also Plate VII. Habit and habitat. On rocks and trees. Vegetative organs (thal- lus). Leaf-like, leathery ; tawny or olive, loosely attached to the surface on which it grows, lobes large, entire, with rounded sinuses; upper surface netted and deeply pitted; under surface pale to white with rounded prominences outlined with slender hairs. Often bor- dered with little white grains (soredia). Fruiting organs (apothe- cia}. Not very common sessile on the margin of the lobes. Name. The specific name pulmonaria, lung, refers to the resemblance the under surface has to the surface of a lung. Sticta amplissima, (Scop.) Mass. See Colour Plate VII. Habit and habitat. On fallen trunks and trees. Vegetative organs (thallus). Extending over quite large areas, in an ever-widening circle appressed to the surface on which it grows; leathery, smooth, becoming wrinkled with age; ashen- green above; tawny, and covered with short, soft hairs (villons) beneath; the lobes elongated, wide, usually compacted, or narrow and repeatedly lobed. Fruiting organs (apothecia). Scattered, sometimes quite large, the disk chestnut; the margin entire and inflexed. Name. The specific name amplissima, the Latin for "very extensive," refers to its habit of growth. 87 Stictina fuliginosa. (o) Upper cortex; () lower cortex; (r) rhizoids; (m) pith layer; (g) gonidial layer. Mosses and Lichens Genus STEREOCAULON, Schreb. The vegetative organ or thallus is two-fold, consisting 01 a scale-like (squamulose) or granulose, horizontal growth which usually disappears, and a vertical growth which becomes shrub- like, with fruit-bearing branches (podetia). The podetia are solid and clothed more or less with a white powder (soredia) and with granules (phyllocladia) which become scale-like or pass into coral-like branchlets. The fruiting organs (apothecia) are at first little disks soon becoming convex; solid, terminal, or lateral; dark-brown, or black. The generic name Stereocanlon is compounded of the Greek o"re/)09, solid, and /cauXo?, a stalk. When dry these lichens are very brittle, but when moist they may be handled freely. Stereocaulon paschale, (L.) See Plate VIII. Habitat. On rocks. Vegetative organs (thallus}. Primary, usually wanting. Secondary, growing in round thick mats; podetia long and slender, much branched and covered with scale-like (squamulose'), crenate, dark-gray granules and inconspicuous cottony fibres. Fruiting organs (apothecia). At or near the apicus of the podetia, small, with disk convex dark-brown. Name. The specific name paschale is the Latin for "Pass- over." Its significance is not evident. NOTE : 5. paschale is closely related to 5. tomentosum which is as its name implies conspicuously covered with cottony fibres. Genus CLADONIA, Hoffm. The horizontal thallus of the Genus Cladonia is scale-like, rarely granulose; and may or may not persist. The fruiting branches (podetia) are hollow, sometimes opening to the exterior; leathery, cup-shaped, or funnel-shaped; some- times shrub-like, and very much branched; rarely club-shaped. The fruiting organs (apothecia) are usually little heads (cepha- loid) hollow within, they are variously coloured, but never black. The spores are ovoid-oblong; simple; colourless. The generic name Cladonia from the Greek, /cXaSo?, a branch, 88 Lichens, Genera and Species was given by Georg Franz Hoffman to describe the characteristic habit of growth. Brown-fruited Cup Cladonia, Cladonia pyxidata (L.) Fr. See Colour Plate XII. Habit and habitat. On stumps and on the earth. Vegetative organs (thallus). Primary, thallus scale-like and variously lobed. Fruit-bearing branches (podetia) hollow, 5 to 25 mm. tall, top-shaped, short-stalked, granulose, warty or scurfy; margin spreading, bearing sessile or stalked apothecia. Fruiting organs (apothecia). Brown. Name. The specific name pyxidata, suggested by the pode- tia, is derived from the Greek irvgis, a small box. The Fringed Cladonia, Cladonia fimbriata, (L.) Fr. See Plate IX. Habitat. Earth, stumps, etc. Vegetative organs (thallus). The primary commonly per- sistent as little scales variously incised on the margin, sea-green above, olive to white or dusky below; often powdery (sorediate). Fruiting organs (apothecia). Brown, sometimes on tooth-like projections of the goblet-shaped podetia. Fruit-bearing branches (podetia). Hollow, i to 3 cm. tall, goblet-shaped, rather long-stalked and slender; the margin erect, often with tooth-like projections sometimes bearing fruits (apo- thecia) ; surface (cortex) disintegrating into a fine white powder. Name. The specific name fimbriata, the Latin for "fringed," refers to the margin of the goblet-shaped branches. The forms of Cladonia fimbriata are extremely varied and difficult to deter- mine. Dr. Wainio recognises sixteen varieties and a large number of sub-varieties, twelve varieties are well known in North America. The Scarlet-crested Cladonia, Cladonia cristatella, Tuckerm. See Colour Plate XII. Habit and habitat. Dead wood, etc. Vegetative organs (thallus). Coral-like (dadoniaform); fruit- ing branches (podetia) hollow, cylindrical, sometimes branched, 2 to 4 mm. tall; smooth or with the surface wrinkled. Fruiting organs (apothecia). Scarlet knobs at the tips of the fruiting branches. Name. The specific name, cristate! la, suggested by the bright fruits, is derived from the Latin crista, a crest. 89 Mosses r.nd Lichens Reindeer Lichen, Cladonia rangiferina, (L.) Hoffrn. See Colour Plate VIII. Habit and habitat. On earth often covering extensive areas. Vegetative organs (thallus). Shrubby (fruticulose). Fruit- ing branches (podetid) 4 to 10 cm. tall, branches cylindrical and hollow, 5 to 1.5 mm. thick, the divisions mostly wide-spreading; the sterile tips curved and drooping; without a distinct outer layer (ecorticaie), the surface fibrous sometimes mealy or warty; ashy-white or tinged with greenish straw-colour. Fruiting organs (apotliecid). Tiny brown knobs on the tips of the fruiting branches. Name. "Reindeer lichen" because reindeer feed upon it in winter. The Cornucopia Cladonia, Red-fruited Cup Cladonia, Cladonia cornncopioides, (L.) Fr. Habit and habitat. On the earth. Vegetative organs (thai his). Branching like coral cladonice- form) ; fruiting branches {podetid) hollow, elongated-top-shaped, about 15 to 35 mm. tall; smooth, becoming warty. Fruiting organs (apotliecid). Scarlet knobs on the tips of the fruiting branches. Name. The specific name cornucoptoides,^suggested by the podetia, is compounded of three Latin words: cornn, a horn, copia, plenty, and oid, like. 90 MOSSES AND LICHENS PLATE VI M i im- . > PARMELIA PERLATA, (L.) Ach PART THREE HEPATICS LIVERWORTS OR HEPATICS HEPATIC/E Liverworts are as a rule found only in damp shady places, and it is not their habit to occupy very large areas of ground. With but few exceptions the plant lies close to the object upon which it grows holding to it by short hair-like cells (rhi^oids). Excepting the fruiting portion, the liverwort plant (the vege- tative body) is either ribbon-like (thalloid), or a stem with scale- like leaves (f otiose); the greater number of liverworts are therefore distinguished as thalloid and foliose. RIBBON-LIKE OR THALLOID HEPATICS Genus MARCHANTIA, (L.) Marchantia polymorpha (See Colour Plate XIII) is a good example of a thalloid form, and from it one may learn, without a microscope, the principal parts. Vertical section through Gemma. showing pore. a pore. Gemma. , Surface view Marchantia polymorpha The plant itself lies flat upon the earth and has a distinct upper and lower tissue. The lower tissue develops short root-like hairs which serve to anchor the plant. The upper tissue appears as if marked off into small rhom- boidal spaces in the centre of each of which a pore may be seen. 93 Mosses and Lichens Little cups are often present on the upper surface, with green disks (gemmae) in them. Upright umbrella-like growths on which are borne the male and female organs are found also on the upper surface. Spor-cas. False p tTiaflth. .Peduncle. Marchantia polymorpha. Vertical section of female receptacle. The male peduncle is capped with a flat, slightly lobed receptacle. The female peduncle is capped with a receptacle bordered with deep finger-like lobes. The male organs (antheridia) are developed in the upper surface of the scalloped receptacle. perianth. ...Jiftii. . -Pedicel,, .._Spre-case. ..L fclaters. A spore- case shedding its spores. Seepage 95. Elater. Under-surface view of female receptacle. Marchanlia polymorpha. The female organs (archegonia) are developed on the under surface of the receptacle bearing the finger-like lobes. Spore-cases filled with spores and spirally twisted threads (elaters) later occupy the place of the archegonia between the long lobes. 94 Liverworts or Hepatics A veil (calyptra) surrounds the spore-case. A false perianth surrounds the veil. A fringed covering (involucre) encloses all the spore-cases between two lobes. When the spore-case is mature, it bursts irregularly for the scattering of the spores. The spore germinates to form one cell or a small group of cells (protonemd) from which later will be developed the plant already described. Marchantia polymorpha. Vertical sec- tion of male receptacle. See pags 94. Marchantia polymorpha. Vertical section of Antheridium from male receptacle. Sperm cells at the right. Marchantia polymorpha, (L.) Habit and habitat. Along wet banks, in bogs, beside streams, about green-houses, and on damp ashes on the shady side of houses. Name. The generic name Marchantia was given by the son in honour of his father, Nicholas Marchant, a French botanist who died in 1678. The specific name polymorpha is com- pounded of the Greek, 73-0X1)9, many, and popfyr], form. Plant (gametophyte) . Peculiar dull-green, with broad ribbon- shaped thallus generally once or twice forked. Costa or mid- vein broad. Upper surface divided off into rhomboidal spaces (areolce). One stoma or pore in the centre of each rhomboidal space. Gemmae cups, saucer-shaped with toothed margins, are often present. 95 Mosses and Lichens Section of plant. (i) Shows well-marked epidermis. (2) Shows that each pore leads into an air-chamber. (3) That the side walls of each air-chamber support the epidermis as a roof. (4) That cells containing chlorophyll spring up from the floor of each chamber. These cells assimilate gases which enter the air-chamber through the pores, they also take in oxygen gas and give out carbon-dioxide gas. The floor-cells transmit or store up food. CCiU. Marchantia polymorpha. Vertical section through the thallus at a point where a pore occurs. Habit of flowering. Antheridia or male organs are imbedded in the upper surface of a shield-shaped, radially lobed disk sup- ported by a peduncle and bearing scales on the under surface. This male receptacle (androecium) grows from the upper surface of the thallus. Archegonia or female organs are borne on the under side of a radially lobed disk supported upon a peduncle on the upper surface of the thallus. The lobes are finger-like, 8 to n, usually curved downward. Section of male disk. Shows antheridia con- cealed in depressions in the surface of the disk. Male flowers (antheridia). Oval upon a pedi- cel (seta). Section shows a wall and numerous cells containing spermatozoids, each with two fine cilia. Section of female disk. Shows archegonia on the under side of the disk. 96 Marchantia polymorpha. In ascending order the cuts show stages in the de- velopment of an antheridium. MOSSES AND LICHENS I PLATE VII SPOTTED LUNGWORT, Slicta pulmonaria, (L.) Ach. . . " a sure cure for lung trouble " Liverworts or Hepatics Female flowers (archegonia). Flask-shaped. Cuts i, 2, 3, 4, 5, 6, 7, 8, show stages in development. Section in early stage, i, shows a wall of cells ; an egg-cell and canal-cell in the i. The false peri- anth is growing down to en- velope the old archegonium wall. 8. The false perianth en- velopes the archegonium wall. enlarged base of the flask ; a canal in the neck of the flask and the summit of the neck closed. Section in a later stage, 6, shows a wall of cells: the egg-cell rounded up; the canal-cell shrivelled; the canal open at the summit of the neck. ....Ta.lsc. perianth. . .J/ti.L ..-, -Pedicel,, Spore-case, ...Slaters. Gemma. Spore-case discharging spores. Marchantia polymorpha. Development of sporophyte. A section, 7, of the archegonium after the spermatozoids have entered and fertilised the egg-cell shows the wall of the enlarged portion of the flask surrounded by an involucre, made up of segments, awl-pointed and finely cut, into an irregular fringe often reddish in colour; the egg-cell is divided into eight cells; the summit of the neck is shrivelled. Section later, 8, shows the eight cells multiplied to form an upper 97 Mosses and Lichens portion, the future spore-case and a lower portion, the future foot and pedicel. Spore-case. At maturity is exserted, when it bursts some- what irregularly to discharge its spores. Spores. Yellow, nearly smooth, mingled with twice-spiral elaters. JFoot eloittrs. Lp ore - wall ftrche^ont unuwoll M. polymorplia. Gemmae. Receptacles bowl-shaped, on the upper-surface of the thallus, and open at the top. Gemmae flat, upright cellular bodies with two indentations at the sides, the growing points. When gemmse germinate, the side toward the light develops pores (stomata) for the admission of gases and for the egress of gases and water vapour. If germination takes place on land, the stomata are on the upper surface, but if in water lighted from below, then they are on the under surface. Gemmae are a means of reproducing plants. 98 MOSSES AND LICHENS PLATE VIII STEREOCAf L()X PASCHALE, L. A gray lichen with black fruits Liverworts or Hepatics LEAFY HEPATICS, SCALE MOSSES, OR FOLIOSE HEPATICS Porella platyphylla (See Colour Plate XIV), is a good ex- ample of the foliose or leafy hepatics and from a study of it one may become familiar with the conspicuous parts of this class of mosses. Margins irregular. Margin inrolled. Leafy hepatics. Margin toothed. The plants grow flat upon the bark of living trees. Each plant consists of a creeping stem, with side branches which may in turn bear branches. The principal leaves are set at right angles to the stem and their sides overlap so as to conceal the stems. They are two-lobed with one lobe above the stem and one below. A third row of leaves grows on the underside of the stem. Two leaves showing lobe and lobule. Creeping stem and branch. Under view of stem showing third row of leaves. Porella plalyphylla. In some leafy hepatics, the tips of the leaves overlap the base of the leaf in front; in others the tips of the leaves are under- neath the bases of the leaves in front. The margins of the leaves of different species vary, they are recurved, toothed, fringed, inrolled, or entire. The apex may be blunt or pointed or of many other designs. 99 Mosses and Lichens The male organs (antheridia) are borne in the axils of the leaves of modified branches. The female organs (archegonia) are on the terminal branches. ....To.lsi perianth. .Spore-cast. filaUrs. Marchanlia polymorpha. One leaf magnified to show cell structure. Porella platyphylla. Male branch. The spore-cases with their enveloping parts are terminal on the branches; although they appear often to be on the sides because a side branch has grown in the same direction and beyond the main stem. .Perianth. .Vtn. Vttl Veil Female branch. Young Sporophyte. Sporophyte. Porella platyphylla. Beginning with the spore-case as a centre, and observing the parts in order outward, a veil (calyptra) may be found, and then a perianth, and outside of all, several slightly modified leaves. Genus PORELLA, (L.) The Genus Porella is composed of large plants, dark-green to yellowish-brown, usually 2 to 3 times feather-branched. The lobes of the leaves are very deeply two-parted; the dorsal large, and roundish egg-shaped, usually entire, the ventral lobes smaller, sometimes nearly separate from the dorsal, varying in different species from ovate to lanceolate; underleaves large, entire or toothed. loo Liverworts or Hepatics The antheridia are spherical, in the axils of overlapping leaves which form short rigid branches. The perianth is oval to obovate, flattened at the mouth, which is fringed, toothed or entire. The spore-case is spherical to ovoid-oblong on a short stalk (seta) splitting nearly to the base into four parts. The spores are covered with spines. The elaters are once to thrice spiral. The generic name is a diminutive of the Latin porus, a pore. Its significance is not evident. Porella platyphylla, (L.) Lindle. Plant (gametophyte). Stems 2 or 3 inches long, prostrate, rigid with the tips bent upward; i to 3 times regularly or irregularly pinnate; root-hairs in tufts at the base of the under-leaves. View of upper surface of stem with two leaves. Two leaves showing 1 obe and lobule Under view of stem. Porella platyphylla. Leaves. Deeply two-parted, dorsal lobes overlapping in two rows so as to conceal the stem, obliquely placed relatively to the stem, oval to oblong, apex obtuse, toothed or entire. Ventral lobes oval to oblong obtuse, diagonally pressed to the surface of the upper lobes; margins recurved and entire or with a single tooth at the base; under leaves tongue-shaped, parallel with the stem, margins recurved, decurrent, entire, or sparingly toothed at the base. Name. The specific name platyphylla from the Greek TrXaru?, flat, and QvXXov, a leaf, describes the prostrate habit of the plant. Perianth. Ovate, inflated, narrowed above, margin toothed with a notch on one side. Veil (calyptrd). Persistent, globose, splitting above. Spore-case. Pale yellow-brown on a short pedicel, splitting into four, often irregular valves; elaters bi-spiral. Spores. More or less spiny. 101 Mosses and Lichens Habit of flowering. Male flowers (antheridia) and female flowers (archegonia) on separate plants (dioicous). Antheridia. Spherical, short-stalked, single in the axils of two-lobed, pouch-shaped leaves which lie opposite on the stem. These antheridial leaves are united by their margins to the under leaves, and with them form short oval branchlets on the sides of the main branches. Archegonia. --Numerous, terminal on very short lateral branches. Genus FRULLANIA, Raddi The plants are usually in shades of red or brown or even black, although sometimes green. They grow in delicate tra- ceries over the bark of trees or rocks. F. ecklonii, A lobule separated from its lobe. A tiny styluses present at the point where the lobule is attached to the main stem. F. ecklonii. Under view of a portion of the stem ; with eight inflated lobules, each on its lobe, the amphigastra have been removed. F.complanata. Under view of stem showing 3 cup-like lobules each lying on its lobe: two notched amphigastra are on the stem. The stems are opaque and branched, each branch arising from the axil of a stem-leaf from which it is always free. The upper leaves are alternate and are inserted somewhat obliquely. They are two-lobed, one lobe folded to lie over the other. The upper and larger is known as the lobe and the lower and smaller as the lobule. The lobule, is an inflated water-sac, in shape resembling a helmet or hood or cylinder and often has at the base a tiny pro- cess (stylus). 102 X Id < SH w K U a c. o a <. 2 s