p- i ru ! 3- : -D ° _ a — a B E P O E T ON THE SCIENTIFIC RESULTS OF THE VOYAGE OF S.Y. 'SCOTIA //r SCOTTISH NATIONAL ANTARCTIC EXPEDITION. RE PO E T ON THE SCIENTIFIC RESULTS OF THE VOYAGE OF S.Y. "SCOTIA" DURING THE YEARS 1902, 1903, AND 1904, UNDER THE LEADERSHIP OF WILLIAM S. BRUCE, LL.D., F.R.S.E. Volume ///.—BOTANY. PARTS I.-XL— By R. N. RUDMOSE BROWN, D.Sc. ; C. H. WRIGHT, A.L.S. ; 0. V. DARBISHIRE, B.A., Ph.D.; JULES CARDOT ; A. GEPP, M.A. : E. S. GEPP; E. M. HOLMES, F.L.S.; M. FOSLIE ; F. E. FRITSCH, D.Sc., Ph.D. ; J. H. HARVEY PIBIE, B.Sc., M.D., F.R.C.P.Ed. Twelve Plates and a CJiart. EDINBURGH: SOLD AT THE SCOTTISH OCEANOGRAPHICAL LABORATORY ; OLIVER & BOYD, EDINBURGH AND LONDON; JAMES MACLEHOSE & SONS, 61 ST VINCENT STREET, GLASGOW. 1912. Price Twenty-tltree Shillings aiui Sixpence in Clotli. EDITORIAL NOT'E. THE author of Flora Antarctica and the pioneer of botanical research in the Antarctic regions has passed away just as this volume was going to press. Our desire, therefore, to dedicate it to him can no longer be fulfilled, nor can we look forward, as we had hoped to do, to his friendly criticism of our efforts in this branch of our researches in high southern latitudes. To Dr R. N. Rudmose Brown have fallen practically all the editorial duties, while little more than publisher's duties, made light by Dr Brown's excellent editing, has fallen upon me. Dr Brown is also the author of Part I., "The Problems of Antarctic Plant Life." He is, with Dr Darbishire, joint author of Part II., "The Botany of the South Orkneys " ; and with Dr Darbishire and Mr C. H. Wright, author of Part III., "The Botany of Gough Island." Part IV., "Contributions towards the Botany of Ascension," we also owe to him. It has been an exceptional chance that three of us who worked together in the field have been able to co-operate in the pro- duction of this Report — Dr J. H. Harvey Pirie, who was bacteriologist to the Scotia, contributing Part X., " Antarctic Bacteriology." My cordial thanks are due not only to Dr Rudmose Brown and Dr Harvey Pirie, but also to Dr O. V. Darbishire, Mr C. H. Wright, M. Jules Cardot, Mr and Mrs Gepp, Mr E. M. Holmes, the late Mr M. Foslie, and Dr F. E. Fritsch. All these have made important and valuable additions to the late Sir Joseph Hooker's Flora Antarctica. It is unfortunate that the Report on the Phytoplankton is not ready to include in this volume, but the rest of the contributions have been already too long delayed for lack of funds ; that Report, in consequence, must stand over for a future volume. WILLIAM S. BRUCE, Editor. EDINBURGH, March 1912. INTRODUCTION. THE botanical results of the Scottish National Antarctic Expedition deal principally with the South Orkney Islands and with Diego Alvarez or Gough Island. From neither of these islands had we any botanical knowledge before the visit of the Scotia,. The South Orkneys were visited twice during the summer, in February 1903 and February 1904, and at Scotia Bay in Laurie Island the Scotia spent the winter of 1903. Numerous opportunities thus presented themselves for making collections of the scanty flora of Laurie Island. On Gough Island the naturalists of the Scotia were able to spend only a few hours ashore on one day, and on that occasion it was impossible to go far inland out of touch with the ship, since the weather conditions were such as to promise a hasty recall. Consequently the collections from Gough Island are in no direction exhaustive. No landing was made on Coats Land, which the expedition had the honour to dis- cover, since none was possible, owing to the lateness of the season and the threatening- nature of the heavy pack in which the Scotia was beset. The marine algfe of the Weddell Sea were most extensively collected through fully 10,000 miles of previously unexplored waters, not to speak of the collections made from Madeira to the Falkland Islands, and from Cape Town to the Azores. The Report on the Phytoplanktou will be published later. Dr Harvey Pirie has added the results of his bacteriological work. A few notes of value on the botany of Ascension are included, based on collections made on the homeward voyage of the Scotia. On an expedition primarily equipped for oceanographical exploration, a botanist cannot look for great opportunities beyond the study of phytoplauktou, and it is with great pleasure that I look back on the invariable thoughtfulness and help of my leader, Dr W. S. Bruce, whenever an occasion for botanical work presented itself. I would take this opportunity of recording my thanks to him and to my colleagues of the Scottish National Antarctic Expedition for the generous assistance they gave me in furthering and in sharing my work on the expedition. Accounts of the greater part of the botanical collections of the Scottish National Antarctic Expedition have appeared at various times in different botanical publications. From these publications they are reprinted, in many cases with additions and altera- viii BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. tions, in the present volume. The following is a complete list of the original papers and their place of publication :— BROWN, R. N. RUDMOSE, "The Botany of Gougli Island: I., Phanerogams and Ferns," Journ. Linn. Soc. Land., Bot., xxxvii. pp. 238-250. Plates. - "The Botany of the South Orkneys : I.," Trans, and Proc. Bot. Soc. Edin., xxiii., part i. pp. 105-110. - " Contributions towards the Botany of Ascension," Trans, and Proc. Bot. Soc. Edin., xxiii. pp. 199-204. CARDOT, JULES, " Les Mousses de 1' Expedition nationale autarctique ecossaise," Trans. Roy. Soc. Edin., xlviii. pp. 67-82. Plates. DARBISHIRE, 0. V., "The Botany of Gougli Island: II. Lichens," Journ. Linn. Soc. Land., Bot., xxxvii. pp. 266-267. " The Lichens of the South Orkneys," Trans, and Proc. Bot. Soc. Edin., xxiii., part i. pp. 108-1 10. Plate. FOSLIE, M., "Calcareous Alga?," KongL Norske Vidensfc. Selsk., Trondhjem (1904), p. 3. FRITSCH, F. E., " Freshwater Alga? collected in the South Orkneys," Journ. Linn. Soc. Land., Bot., xl. pp. 293-338. GEPP, A. and E. 8., "Antarctic Algae," Journ. Bot., April 1905 and May 1905. Plate. - "More Antarctic Algae," loc. cit., July 1905. Plate. - " Atlantic Algae of the Scotia," lor. cit., April 1905. HOLMES, E. M., "Some South Orkney Algae," Journ. Bot., July .1905. WRIGHT, C. H., "The Botany of Gough Island: II. Mosses and Hepatics and Fungi," Journ. Linn. Soc. Land., Bot., xxxvii. pp. '264, 265. - "The Mosses of the South Orkneys," Trans, and Proc. Bot. Soc. Edin., xxiii., part i. (Note. — The two papers by Mr Wright on the mosses are not republished in the present volume, since Monsieur Carclot has redetermiued the mosses of the Scotia, and has entirely superseded previous papers on the subject.) I have taken advantage of the occasion of the republication of these papers to ask the various authors to bring them up to date in the light of the most recent research, and I have added a general discussion of the problems of Antarctic botany. My thanks are due for valuable assistance to the following who have collaborated with me in the work of describing the Scotia botanical collections : — Monsieur Jules Cardot, Dr 0. V. Darbishire, the late Mr M. Foslie, Professor F. E. Fritsch, Mr A. and Mrs E. S. Gepp, Mr E. M. Holmes, and Mr C. H. Wright. I would also record my thanks to Sir W. T. Thiselton-Dyer, K.C.M.G., late Director of the Royal Botanic Gardens, Kew, for permission to make use of the Kew Herbarium ; to Mr W. B. Hemsley, F.R.S., and Professor J. W. H. Trail, F.R.S., for advice on certain points ; and to the Societies in whose publications certain of these papers originally appeared, for permission to reprint. It had been intended to dedicate this volume on Antarctic botany to Sir Joseph Dalton Hooker, the earliest pioneer of botanical investigation in South Polar lands and seas. His death on December 10, 1^11, has prevented this; so all that can be done is to offer these papers as some slight tribute to the memory of that great man. R. N. RUDMOSE BROWN. EDINBURGH, March 1912. CONTENTS. I. THE PROBLEMS OF ANTARCTIC PLANT LIFE. By R. N. RUDMOSE BROWN, D.Sc., University of Sheffield. (With a Chart) 3 II. THE BOTANY OF THE SOUTH ORKNEYS. By R. N. RUDMOSE BROWN, D.Sc., . University of Sheffield, and O. V. DARBISHIRB, B.A., Ph.D., University of Bristol. 23 (With a Plate) ..... III. THE BOTANY OF GOUGH ISLAND. By R. N. RUDMOSB BROWN, D.Sc., University of Sheffield; C. H. WRIGHT, A.L.S., Royal Botanic Gardens, Kew ; and O. V. DARBISHIRE, B.A., Ph.D., University of Bristol. (With Four Plates) . . 33 IV. CONTRIBUTIONS TOWARDS THE BOTANY OF ASCENSION. By R. N. RUDMOSE BROWN, D.Sc., University of Sheffield . . 47 V. LES MOUSSES DE L'EXPEDITION NATIONALS ANTARCTIQUE ECOSSAISE. By JULES CARDOT, Charleville. (With Three Plates) .... 55 \ VI. MARINE ALG.E OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. By A. GEPF, M A., British Museum, and Mrs E. S. GEPP. (With Two Plates) 73 VII. SOME SOUTH ORKNEY ALG^E. By E. M. HOLMES, F.L.S. 87 VIII. CALCAREOUS ALG.E. By M. FOSLIE, Trondhjem Museum . . 91 IX. FRESHWATER ALG^E OF THE SOUTH ORKNEYS. By F. E. FRITSCH, D.Sc., Ph.D., East London College, University of London. (With Two Plates) . 95 X. NOTES ON ANTARCTIC BACTERIOLOGY. By J. H. HARVEY PIRIE, B.Sc., M.D., F.R.C.P.Ed. . 137 XI. BIBLIOGRAPHY OF ANTARCTIC BOTANY 151 311)50 I.-THE PROBLEMS OF ANTARCTIC PLANT LIFE. VOL. 111. I.-THE PROBLEMS OF ANTARCTIC PLANT LIFE.1 By R. N. RUDMOSE BROWN, D.Sc., University of Sheffield. (With a Chart.) THE general belief held until quite recent years that the Antarctic regions were almost destitute of botanical interest and the last place on the earth's surface where plants could be looked for, was amply justified until the closing years of last century. Our botanical knowledge of these regions up to that time was so scanty that almost the only collections known were the few mosses from Cockburn Island, Graham Land, found by Joseph Hooker in Ross's expedition in the Erebus and Terror in 1839-43. The recent renewed interest in the Antarctic, as expressed in the expeditions of the last decade, by various collections and observations, has shown that the south polar flora, poor as it may be, is nevertheless in some respects richer than was supposed, and gives the botanist reason to hope for further results from future expeditions. One of the chief interests in these collections lies, of course, in the questions they give rise to in the problems of geographical distribution, and the origin of the Antarctic flora. It is much to be hoped that future expeditions will make further discoveries in palseobotany. With the exception of a somewhat doubtful fossil of coniferous wood, that may be ascribed to Lower Carboniferous or Devonian times, found in Victoria Land, the only fossil plants we know from Antarctica are the abundant remains brought *f A O back by Dr Otto Nordenskjold from Hope Bay in north-east Graham Land. This flora of ferns, cycads, and conifers indicates a warm, moist climate and abundant vegetation in Jurassic times. The fossil Araucaria, Fagus, and other plants found at Seymour Island by the same expedition, indicate an extension of these conditions into Tertiary times. The adaptations of the various species to their environments, a study particularly important in the case of cosmopolitan species, promises most valuable results, but is more likely to be undertaken seriously when the systematic and geographical interests of the flora have been more fully worked out. For a newer study almost invariably has to wait until the older aspects of the science have been satisfied. It is, moreover, extremely desirable that such physiological and morphological questions should be studied on the spot ; indeed, the impracticability of satisfactory investigation in any other circumstances is most obvious. Dr Fritsch in his remarks on yellow and red snow (pp. 99-120 of this volume) speaks of the absolute necessity of investigating these 1 Certain parts of this article appeared in a less extended form in a previous paper by the same author, " Antarctic Botany : its Present State and Future Problems," Scot. Geog. Mug., 1906, pp. 473-483. 3 4 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. occurrences in the field. The difficulty of laboratory accommodation in the isolated Antarctic regions is naturally great, but not nearly so great as is generally supposed. Various expeditions which have recently wintered in the south have shown that the climatic conditions, though not exactly as favourable as in the north, offer no serious inconvenience to an ordinary robust constitution and cheerful disposition, even though one is not prepared to rough it in the manner of the geographical explorer. And, furthermore, it should be remembered that there are at the present time several habitable dwellings within the regions of south polar ice which have been erected by one or other of the expeditions of the past ten years. Of these the house at Scotia Bay, South Orkneys, is permanently inhabited as an Argentine Meteorological Observatory, while that at Wandel Island has been, or shortly will be, taken possession of for a similar purpose. Thus it will be seen that laboratory accommodation on a small scale in the Antarctic regions is far from impracticable, and should not be a matter of any very great cost. Most of these stations, it may be remarked, are not very far to the south ; but that is a distinct advantage, for while all are within the veritable polar regions and experience the real Antarctic climate, they escape in very large measure the long night and its attendant drawbacks, and, most important consideration of all, they are readily accessible, so that a relieving ship should experience little difficulty in gaining all or any of them every summer. The Danes have now established in north polar regions, on Disco Island, a fully equipped biological laboratory, and the extreme desirability of a similar station in south polar regions need not be further urged. But in the meantime, until this larger project can be put into execution, it would be most desirable that a biologist should be attached to each of these Antarctic observatories, year by year, though, of course, as the number of inhabitants at each observatory must be very strictly limited, he would combine his biological studies with the duties of a meteorological observer. The most striking feature of the Antarctic flora is, of course, its poverty compared with that of the Arctic. Thus the Arctic regions support about four hundred species of flowering plants, while the Antarctic regions support but two, and even these can hardly be said to flourish. The reasons which bring about this extreme contrast between north and south is one of the most interesting biological problems that awaits solution in these regions. The amount of light available is, of course, the same in north and south at corre- sponding latitudes, and yet the contrast between the two vegetations is even more marked when one remembers that in Spitsbergen, in 79° N., the ground is bright in summer with a hundred species of flowering plants, while at the South Orkneys, in only 6T S., there is not a single species. In Grant Land, in 81°-82° N., in three localities, Peary collected 57 mosses and 7 hepatics — a greater number than at present known from the whole of the Antarctic regions south of GO S.1 Snow is probably not much more 1 "Ad cognitionem Bryophytorum arcticorum contributiones sparse," M. Brylm, VidenA, &-M. Fordhandl. (Christiania), 1908, No. 5. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 5 abundant in the south, and winter temperatures, at least in the outermost south polar regions, neglecting for the moment comparative latitudes, are not more severe than iu the north. The real explanation is probably to be found in the short and inadequate Antarctic summer, with its remarkably low temperatures. Thus, for example, at the South Orkneys, in 60° 44' S., the mean of the summer months (December, January, and February) is barely 32° F., and in no mouth does the mean rise to 33° F., while the mean of the warmest day in 1903-04 was only 377° F. ; at Snow Hill Island, Louis Philippe Land (64° 24' S.), the mean of the warmest month (January) was found to be only 30'38° F., while at Cape Adare, Victoria Land, in 71° 18' S., the summer mean is 30 '4° F. At 77° 50' S., 166° 44' E., in McMurdo Sound, the Discovery found that the mean summer temperature was 21 '4° F., and the mean of the warmest month, December, was 24-6° F. These temperatures may be compared with those of the Arctic regions. Thus at Spitsbergen (79° 53' N.) the mean temperature of July (the corresponding month to January in the south) is as high as 4T5° F., while in Franz Josef Land, in over 80° N., it is not lower than 35 '6° F. iu the same month. The mean of the Spitsbergen summer (June, July, and August) is 37'1°, contrasted with the corresponding mean given above for the South Orkneys, scarcely 32° F. Examples could thus be multiplied, but all would bring out the same important point — that while the Arctic summer mean is well above 32° F., the Antarctic summer mean is practically always below. This remarkably cold Antarctic summer acts in two ways upon plant life : firstly, the winter snow lies late on the ground — all the later as the summer is a cloudy and somewhat sunless period, and December is well advanced before the majority of available sites are laid bare, while iu February the winter again begins1 ; secondly, and this is the chief reason, it is doubtful if a flowering plant could obtain the requisite amount of heat needed for its various life functions even to reach the flowering stage, while the maturation of its fruit would be next to impossible. In fact, one could with much truth say that the Antarctic summer is but an astronomical conception : those who have experienced it know well how little reality it has. Doubtless, then, in this want of a season of growth lies a quite adequate explanation of the poverty of the south polar vegetation, but I think that there is also another adverse influence at work. Even supposing that a species did obtain a footing on Antarctica, as is not impossible in the lands nearest Fuegia, considering the narrowness of Drake Strait, its continued existence would be at once menaced by the presence of the myriads of penguins which occupy almost every bare spot of ground during the nesting and breeding season. There is no parallel in the north to these penguins and the power they would have in destroying any vegetable 1 Contrast this with the north, where, for example, at the northern part of the east coast of Greenland, the land is clear of snow from May or early June until September, dates which would correspond in the south to November to March. 6 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. life. Almost every spot where a plant might obtain a hold is covered with these birds in the proportion of at least one to a square yard, and nothing escapes their insatiable curiosity or fails to be examined with their beaks, while in a few weeks' time such a rookery is in an indescribable state of filth, being entirely covered with, several inches of mud and manure through which the penguins are incessantly tramping hither and thither ; circumstances which would render plant life quite out of the question. It is true that here and there one finds a small expanse — even as much as an acre I have once seen — of moss-covered rocks which by successive years' growth are covered with 6 to 8 inches of vegetable soil, but these are spots much less accessible from the sea, and are very seldom suitable for rookeries — which is, of course, the sole condition under which this continuous growth of moss from year to year could continue. In such spots one might look, though in vain, for flowering plants, and perhaps in con- sequence conclude that the influence of the penguins, though potentially inimical to vegetable life, has never cause to operate, at least against flowering plants. But it must be noted that these moss formations, though in many respects suitable for phanerogamic plant life, are yet always very late in losing their winter snow, and generally lie in sheltered places where wind-carried seeds would be little likely to arrive. That seeds of Fuegiau species of phanerogams occasionally reach Graham Land and the adjacent South Shetland and South Orkney Islands is more than probable, considering the prevalence of winds from the north of west in that region : it is even possible, though far less likely, that wind-carried seeds from Kerguelen and Heard Islands occasionally alight on parts of the coasts of Wilkes Land. Most important in relation to the possible wind transport of Fuegian species to Antarctica is the discovery by Dr F. E. Fritsch of pollen grains of Podocarpus among the algse found in a patch of red snow in the South Orkneys. The nearest land from which these pollen grains could have come is southern South America, where several species of Podocarpus occur in Chili, some at high altitudes, and so more likely to have their pollen carried by the wind. I cannot suggest any way in which these pollen grains can have reached the South Orkneys other than by wind carriage, and their presence seems indisputable proof of the possibility of this occurring. In this relation it is noteworthy that Dr Fritsch believes " that the nature of some of the Antarctic freshwater plankton points to wind carriage over considerable distance, although the available data are not sufficient." The likelihood of the transport of seeds by birds is lessened by the fact of there being only one true land bird (Chionis alba) in the Antarctic, but it seems quite probable that seeds and spores are occasionally carried adhering to the feet and feathers of such wandering birds as the southern black-backed gull, the skua, and the giant petrel, which range from sub-antarctic to Antarctic lauds. Almost everywhere that snow-free laud occurs on the coasts of Antarctica in summer, innumerable birds find nesting-places, and these are the places where or near where most of the vegetation occurs. As regards floating ice, I do not think that in the Antarctic it ever acts as an agency in the dispersal of species. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 7 It has been suggested that the conspicuous absence of driftwood on Antarctic shores shows that there is little likelihood of wave-carried seeds being stranded.1 The contrast with the shores of some parts of the Arctic regions is certainly great in this respect. Numerous stretches of the coasts of Spitsbergen have almost the appearance of timber-yards with their acres of timber-stacked beaches. During eight months at the South Orkneys we found only a single small piece of driftwood. But this absence of driftwood can be explained on two grounds : firstly, to currents sweeping past rather than striking the shores of Antarctica, except perhaps the north-west of Graham Land and the South Shetlands ; and, secondly, to an absence of driftwood in the waters of the Southern Ocean. Most of the Arctic driftwood is brought down by the Siberian rivers and the Mackenzie River in flood. A large amount is thus swept into a confined sea. For the Southern Ocean there are no such sources of supply, while the little timber that is swept into the sea is negligible in that vast extent of water. Nor do I think that seeds and spores brought on driftwood and wreckage to Antarctic coasts would stand any chance of stranding on a locus favourable for growth, even supposing they had survived the voyage, and that is most unlikely. It is therefore not by reason of their isolation alone that the south polar regions have next to no phanerogamic vegetation, but because they are unsuited in one way or another to support it. If such a modest biological station, as I have advocated above, should be instituted, it would be a matter of extreme interest to attempt to cultivate on certain of the mossy oases various species of hardy Arctic plants, such as Pa/paver radicaium, Ranunculus sulphureus, Cerastium alpinum, Saxifraga oppositifoha, etc. etc., which all prosper and produce seed in Spitsbergen.2 Dr Skottsberg, of the Swedish Antarctic Expedition, considers that the formidable Antarctic winds must be another unfavourable condition for higher plant life.3 While fully admitting the strength of the winds that sweep over certain localities the greater part of the year, I do not think that they could have an inimical influence on any possible vegetation, partly because there are always certain sheltered spots, but largely because the Antarctic summer is a relatively calm period, while the winds of winter could of course have no prejudicial influence through the covering of snow. ' Polar Exploration, W. S. Bruce, London, 1910, p. 92. 2 On my return from the Antarctic in 1904 I attempted to make such an experiment by sending to the Argentine Meteorological Station at the South Orkneys a supply of seeds of 22 Arctic species of phanerogams, with a request to have them planted in a certain spot which I chose as suitable during my stay at Scotia Bay in 1903. I understand that all the seeds that were planted failed to sprout, but the absence of a biologist on the spot may have militated against the success of the experiment. The seeds sent were all of Arctic species, and it may be as well to publish the complete list, which is as follows -.—Papaver radicatum, Rottb. ; Draba alpina, L. ; D. hirta, L., f. rupestns, R. Br. ; UoMearia officinalis, L., var. 0, Vahl ; Vesicaria eretica, Poir. ; Silene acaulis, L. ; Cerastium alpinum, L. ; Potentilla nivea, L. ; Alchemilla alpina, L. ; Saxifraga oppositifolia, L. ; S. nivalis, L. ; S. rivula.ris, L. ; S. hypnoides, L. ; Rhodiola rosea, L. ; Eriijeron alpinum, L., var. grandiflorum, Eahl. ; Hieracium alpinum, L. ; Vaccinium uliainosum, L. ; Ardostaphylos uva-ursi, Spreng. ; Armeria pubescens, L. ; Oxyria rcniformis, Hook. ; 0. elatior, R. Br. ; Luzula spicata, Desv. 3 "On the Zonal Distribution of South Atlantic and Antarctic Vegetation," Carl Skottsberg, Geog. Journ. Dec. 1904. 8 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Before turning to a consideration of the actual vegetable life of the Antarctic, especially as revealed by the expeditions of the last few years, it would be advisable to define the limits of the Antarctic regions from a phytogeographic standpoint. On this subject there has been much diversity of opinion, largely attributable to an almost complete ignorance of the conditions obtaining in the south. In an able discussion l of the whole question, Dr Skottsbcrg clearly points out the obvious error that phytogeographers commit in placing the boundary of the Antarctic regions too far to the north so as to include, according to some, even part of South America : as untenable a position as that of those who would restrict the Antarctic to the regions south of the astronomical Antarctic circle. Dr Skottsberg shows that the parallel of 60° S. forms a more or less natural limit, and in this proposition of his I quite agree. The South Orkneys without a doubt are truly Antarctic in all respects, but South Georgia is sub-antarctic, and so in all probability is the South Sandwich group. The flora of the Antarctic regions as thus defined contains only two phanerogams, viz. Descampsia antarctica (Hook.), Desv., and Colobanthus crassifolius , Hook. f. var. l)i'evifolius, Eng. The former of these has long been known from Antarctic regions, having been collected by Eights about 1820 at the South Shetlands, and it also occurs on several parts of Graham Land; but its discovery, along with Colobanthus crassifolius, by Dr Turquet, of the French Antarctic Expedition (1904-05). at Biscoe Bay, Anvers Island, in 64° 50' S., 63° 40' W., was very interesting, for this was the most southerly record for flowering plants known. Descampsia antarctica was also found by Dr Turquet at Wandel Island, 65° 4' S. Dr Charcot's expedition in the Pourquoi Pas? in 1910 found these two species of flowering plants as far south as 68° S. Both these phanerogams occur also in Fuegia, the Falkland Islands, and South Georgia. Eeference has been made by me elsewhere ~ to the reputed grass of the South Orkneys, of whose occurrence we have no evidence except the vague report of a sailor, and which I know from personal search does not grow to-day in the place indicated. Ferns are entirely wanting in the Antarctic, as was only to be supposed, but mosses are relatively abundant and form almost the chief constituent of the flora. Collections 3 of these are known from various points around the pole, including Graham Land, South Shetlands (Belgica, Antarctic, Franqais, and Pourquoi Pas?}, South Orkneys (Scotia and Argentine Expedition), Wilhelm Land (Gauss), and Victoria Land (Southern Cross, Discovery, and Nimrod), but those from the Atlantic and American sides are incontestably the richer, no doubt largely because of the nearer proximity of extra-polar land and consequent possibility of migration, but also to some extent because that side of the 1 "Some Remarks upon the geographical distribution of vegetation in the colder Southern Hemisphere," Carl Skottsberg, Ymer (Stockholm), 1904, pp. 402-427. This paper also contains a useful bibliography of Antarctic anrl sub-antarctic botany. 2 See this volume, p. 24, and "The Botany of the South Orkneys," R. N. Rudmose Brown, Trans, and Proc. Bat. Soc. Edin., xxiii. i. (1904-05). 3 See paper by J. Cardot in this volume, pp. 55-69, and " La flore bryologique des Terres magellaniques de la Georgie du sud et de 1'Antarctide," J. Cardot, IVissen. Erg. Schwed. Sudj>olar-Exp., iv. 3. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 9 Antarctic regions has received more careful and serious exploration than any other. Graham Land, moreover, extends to a far lower latitude than other parts of Antarctica. The total number of mosses brought from Antarctic regions up to and including the collections of the Nimrod, appears to be 52. The Belgica collected 27 species on the west of Graham Land, the Antarctic 23 in different parts of Louis Philippe Land and adjacent regions, the Frangais 18 round about Gerlache Strait, and the Scotia 10 at the South Orkneys. Four further species were collected at the South Orkneys by Senor L. H. Valette of the Argentine Observatory (1904). Of the 14 South Orkney species none are endemic, but 4 are not known from outside the Antarctic regions. The Southern Cross collected 3 species in Victoria Land, the Discovery added 6 further ones to this list, and the Nimrod one more. The Gauss collected only one species of moss at Wilhelm Land, and this at present is the only one known throughout the whole extent of coast-line between Cape Adare and Graham Land. The Scottish Expedition was unable to effect any landing on Coats Land. Dr Cardot has recently discussed in full the relationships of the moss flora of the Antarctic (loc. cit.). He points out that 24 of the 52 species are endemic, 16 are northern and 12 southern species of wide distribution, while the rest are more or less cosmopolitan ; and noting also that many Antarctic species have close affinities with northern species, concludes that " en somme la facies de la flore bryologique antarctique est plus boreal que magellanique." Dr Cardot believes that the Antarctic moss flora will be found to be very uniform wherever it occurs. Of the 9 species known from Victoria Land, 5 are peculiar to Antarctic regions, and 3 of those are also found in Graham Land. In all, 6 of the 9 species found in Victoria Land are common to both it and Graham Land : this is a high proportion. Again, the relationship of the Antarctic moss flora with those of South Georgia and the Magellan lands is most noticeable. There are 17 species common to the Antarctic and South Georgia, of which 6 are of wide distribution in other lands, chiefly northern : 16 species are common to the Antarctic and Fuegian lands, of which 10 are of wide distribution, again chiefly in the northern hemisphere. Excluding 8 species of wide distribution, only 5 species occur in both the Antarctic and Kerguelen, and of these 3 are also found in South Georgia. These facts suggest a migration from Fuegian lands as the origin of the Antarctic flora. The life conditions for mosses are evidently not too unfavourable, for most of the species show a fairly vigorous growth and do not appear to suffer from the severe environment. Dr Cardot comments on the luxurious growth of certain specimens sub- mitted to him. This can specially be remarked in those species which have a wide distribution throughout other parts of the world, for in them it is possible to make a comparison of the effects of the Antarctic climate and soil on the growth of the plant, In the South Orkneys I noticed that for at least seven months, and in places eight, the moss was frozen as hard as rock, but this did not seem at all to impair its vitality on VOL. III. 2 10 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION the return of spring : farther south — and mosses have been collected in the far south of Victoria Land (78° S.) — their frozen condition must last longer. In this relation it is striking how poor and stunted are the specimens from 77° to 78° S. in Victoria Land compared to those from lower latitudes in Graham Laud. Vegetative reproduction among Antarctic mosses seems to be the rule, and fruiting specimens of most species are very rare among the collections of all the expeditions: among my South Orkney specimens the only species with many and well-developed fruits was Polytrichum sub- piliferum, Card., and Dr Cardot says that among all the species of Antarctic mosses he has seen only 6 in fruit : in a few other species "flowers" have been seen. Antarctic mosses generally grow in small colonies in which a number of different species may be found together. In the midst of these clumps an occasional hepatic may be found, for hepatics seldom if ever grow isolated, nor indeed do individual species of moss. Doubtless this is the only habitat in which hepatics with their more delicate tissues could survive. In some cases a small tundra of moss and lichen vegetation may be formed, and since these tundras are used as nesting-places by skuas and gulls, while other birds, as shags, build their nests largely of moss and lichen, one can understand the dispersion of the flora by this agency. This habit of aggregation which Antarctic mosses have, shows the need of exhaustive collecting : a mere sample or two of a clump is not sufficient, and a collector new to the Antarctic will invariably overlook many species by not taking numerous enough samples of each colony. The number of Antarctic hepatics is naturally not great, and includes not more than 6 species, of which 3 are found in Gerlache Strait, 1 at the South Shetlands, and 3 in Orleans Channel. In the South Orkneys no species was discovered, nor was any found in Wilhelm Land or Victoria Land. Of these 6 hepatics, 4 occur in South Georgia, While several fungi are recorded from sub-antarctic islands, such as Tristan da Cunha, Gough Island, and others, the true Antarctic regions support but a single species, the discovery of which was made by M. Eacovitza of the Belgica; this was a new species, Sclerotium antarcticum, Bomm. et Eous., and was found on Danco Land growing among Aira antarctica : apparently this is its only record. Undoubtedly the predominant feature of the Antarctic vegetation is the number of lichens, not as species, but as individuals. At the South Orkneys the lichen vegetation is very rich. In winter, when almost everything is deep in snow, a few precipitous rock faces still show a relieving touch of colour among the monotonous white, due largely to various orange-coloured species of Placodium (P. regale, Wainio, and P. elegans, Nyl.) : when the snow begins to melt in spring almost all the rocks bared to view show a shaggy covering of Usnea melaxantha, Ach., a species which more than any other seems to luxuriate in the conditions of life to be found there, and produces good " fruits " in quantity. Dr Skottsberg also mentions the frequency of Placodium and Usnea in the lands he visited, and M. Turquet notes1 the colour given to the landscapes of Gerlache Strait and Graham Land by Usnea and Lecidea. M. Gain 1 Le Franfais cm Pdle, Surf, J. Charcot, Paris, 1906, v., " La Vie vegetale," pp. 434-438. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 11 of the Pourquoi Pas ? speaks l of the almost continuous carpets of Usnea at Deception Island. Two other species, Rhizocarpon geogr.aphicum, D.C., and Letideafusco-atra,, Th. Fr., are less abundant, and owing to their more sombre colour and less striking appear- ance do not, as a rule, lend any very characteristic feature to the landscape. The number of Antarctic lichens so far known is 88, but the reports on several recent collections have yet to be published. Future exploration will certainly add greatly to this number. Eleven species were found by the Scotia at the South Orkneys, and with regard to these Dr 0. V. Darbishire reports 2 that all except one were previously recorded from some part of the Arctic regions, and that, taking into account all known collections, the pro- portion of Arctic species is as high as 73 to 75 per cent. Of the Discovery collections 76 per cent, were also Arctic in distribution. The lichens of Gerlache Strait as collected by the Belc/ica numbered 55, including a new species of Placodium (P. regale, Wainio), which was also found by me at the South Orkneys and independently described as P. fniticulosum, Darbish.: Wainio's name, however, has priority. Of these 55 species 38 '2 per cent, were known from Arctic regions, and as many as 527 per cent, were new. All the 3 species recorded from Wilhelm Land are of wide distribution. Since these statistics include in each case many cosmopolitan or very widely spread species, which are common among lichens, it would be unwise to base on them arguments concerning the origin of the Antarctic flora, The multicellular algae of Antarctic seas are quite abundant as regards individuals, if perhaps the species are not very numerous. Fifteen species are recorded by Mr and Mrs Gepp from my South Orkney collections, and Mr Holmes records 9 other species in a small collection made by the expedition in the same place. Of the species deter- mined by Mr and Mrs Gepp, 5 are new. I am confident that careful exploration of the coasts of these islands at seasons when they are free from ice would reveal many more species. As was only to be expected, the littoral region, i.e. the area between high and low water, proved poor both in individuals and species ; calcareous species are the most abundant in that region. The wearing and tearing action of the ice is not compatible with much algal growth in these shallow waters, and this no doubt accounts for the absence of the southern kelp (Macrocystis pyrifera) from the true Antarctic regions. The majority of the algse occur at greater depths. The daily haul of the dredge which we took in Scotia Bay scarcely ever failed to bring up specimens of algse, The two red algse (Plocamium coccineum, Lyngb., and Acanthococcus spinuliger, Hook, and Harv.) were extraordinarily abundant in 10 fathoms, and the brown alga (Desma- restia Rossii, Hook, and Harv.) was frequent in shallower water. Calcareous algse were obtained almost daily in 9 to 10 fathoms. In places these algse cover the rocks in a few feet of water with so continuous an incrustation that at first sight one is deceived into the belief that it is an ice formation. Probably the most interesting find 1 Rapports pr&imina/ires sur les travaux executes dans I'antarctique, Academic des Sciences, Paris, 1910, p. 99. 2 See this volume, pp. 24-29, and " The Botany of the South Orkneys : Lichens," O. V. Darbishire (loc. cit.). 12 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. among the Scotia algae was the new species Phyllogigas simulans. This was first described (loc. cit.) by Mr and Mrs Gepp from material I collected at the South Orkneys. Since then it has also been found at Graham Land and South Georgia by Dr Skottsberg, and another species (P. grandifolia) has been recorded by the Discovery from Victoria Land. It is a genus whose species have some similarities in habit to that of the " kelp," although it is anything but abundant. Our knowledge of Antarctic multicellular algse is practically confined to the Graham and Victoria Land regions ; and though most of the collections are now published, it would be rash to draw any deductions of a distributional nature ; for while the Graham Land region has been the more carefully explored of the two, neither can be said to be known thoroughly as regards its algse. Some 40 species are at present known from Antarctic seas, of which about 75 per cent, occur at Graham Land, and about 40 per cent, at Victoria Laud. Dr Skottsberg has discussed in various papers (see Biblio- graphy) the distribution of these algse as far as is possible, and he finds that no facts in this realm of botany support the idea of bipolarity. Only one species of freshwater alga (other than unicellular and colonial algse) is so far known, viz. the cosmopolitan Prasiola crispa, Ag., which is recorded from both Graham Land and the South Orkneys.1 In the latter place it was to be found in summer and autumn in several small gulleys where a quantity of melting snow above assured a continual supply of moisture. Unicellular algse naturally form the vast preponderance of the botanical treasures of the Antarctic regions. When once the regions of ice. are approached, between 50° S. and 60° 8., the plankton entirely changes its character; crustaceans, and in fact all animals, then become rare, and give place to increasing numbers of diatoms until, in the midst of the ice, the diatoms occur in such prodigious quantities that five minutes' haul of the tow-net (No. 20 miller's gauze) produces as much as a pint of gelatinous residue almost wholly diatomaceous. The fact that such a net, used about thrice daily on the average, ceases to be serviceable after about a week or ten days' use, owing to the clogging of the apertures in the silk, will give an idea to anyone accustomed to plankton work of the wealth of diatomaceous life in these seas. The species are not very varied, but a large proportion of them bear spines and long arms, while simple forms are comparatively rare. Peridineans occur, but only rarely. The phytoplankton on the whole seems to favour deep water, for in the shallow water about the South Orkneys it was much scarcer. In winter the greater part is apparently frozen into the ice, for 1 failed to get any appreciable quantities from the water on the occasions when I bored the floe with this object in view. The first-formed pancake ice is always yellow, and the lower layers of the floe as revealed in the spring upheaval are uniformly discoloured by a layer of diatomaceous ice. In no part of the Antarctic seas visited by the Scotia did I observe the open water 1 Some authorities recognise Prasiola antarctica, Kiitz, in addition to P. crispa, in Antarctic lands. See " Fresh- water Alg;e," W. and G. S. West, Brit. Antarct. Exped. (1907-09), 1911, vol. i., and F. E. Fritsch, p. 128 of this volume. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 13 discoloured by diatoms, and I am not aware that other recent expeditions have recorded this occurrence ; but Dr W. S. Bruce, in the cruise of the Balsena in 1892-93 between 62° and 63° S., off Louis Philippe Land, frequently remarked that the sea was olive- green or olive-brown from this cause, and that the most usual species in these dis- coloured parts was Corethron criophilum. This phenomenon is of much commoner occurrence in Arctic seas.1 Plankton collections well within Antarctic seas and over a wide area are largely confined to the collections of the Scotia, which fortunately was able to traverse some 10,000 miles of unexplored south polar waters. The other recent expeditious, Discovery, Antarctic, Gauss, Frangais, and Nimrod, did comparatively little marine exploration within truly polar waters. The Belgica's results in this de- partment should, however, be of great interest, and will be supplemented by those of the Pourquoi Pas?, while the Vnhlivia's collections, though in more or less extra-polar waters, have important relation to Antarctic plankton. A detailed report and discussion of the Scotia's plankton is in process of completion. While freshwater algae appear to be comparatively abundant, they are not nearly so plentiful as in north polar regions. In the collections which I made at the South Orkneys, Dr Fritsch has found 68 species (of which 5 are new) : most are uni- cellular and colonial.2 With the exception of the Belgica, the Southern Cross, the Discovery, and the Nimrod, other expeditions have not yet published their results in this branch of botany. A number of forms, however, have been recorded from Kerguelen and South Georgia. Among the South Orkney collections very few reproductive stages were found even in material collected about midsummer, and Dr Fritsch believes that many species only reproduce during very limited periods under specially favourable conditions. The rarity of diatoms and infrequence of desmids in this freshwater flora are noteworthy None of the new forms of diatoms in either the Discovery or Nimrod collections occur at the South Orkneys. Red and yellow snow occur at the South Orkneys, though neither is abundant. Red snow has been recorded from Arctic regions, as well as other parts of Antarctic regions, including Graham Land and Victoria Land : it is also recorded from extra-polar regions. Yellow snow is much rarer, and I am not aware that other Antarctic expeditions came across it. Dr Fritsch has reported in considerable detail on these coloured snows (he. cit.), and he finds that yellow snow is due to an association of 1 8 species of algae and 2 of fungi ; most of the algas are green forms, but few diatoms occur. The whole of this flora has a plankton character, and Dr Fritsch suggests that this and other snow floras may have arisen by wind carriage of plankton forms to the snow surface. Most of the constituent members of this flora have a quantity of fat in their cell contents, in which yellow pigment occurs. This fact seems to be an adaptation to the severity of the habitat. 1 "On the Nature of the Discoloration of the Arctic Seas," Robert Brown, Trims. Bot. Soc. Ediii., ix. p. 244. 2 See this volume, pp. 95-134, and "Freshwater Algre collected in the South Orkneys," Joan/. Linn. Soc. Land xl., 1912, pp. 293-338. 14 BOTANICAL RESULTS OP THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. The red snow of the South Orkneys is also due to an algal association, but one that is considerably poorer both in species and individuals than that causing yellow snow. Most of the algal forms seem to contain fat in many of their cells. While the red colour of these South Orkney samples appears to be due, as in the case of Arctic occur- rences, to Chlamydomonas nivalis (Spliaerella nivalis], it is difficult to say definitely in preserved material. Mr James Murray believes that the red snow of Victoria Land is sometimes due to red rotifers, whose abundance in the Antarctic he was the first to demonstrate. Red rotifers were found in Agassiz' red snow from the Alps, but have not been recorded from the South Orkneys. The red colour Mr Murray ascribes to the nature of the food. Elsewhere in this paper (p. 6) I have commented on the signi- ficance of Dr Fritsch's discovery of pollen grains of Podocarpus in the red snow, as proof of the occurrence of wind transportation from adjacent lands to Antarctica. Such, in outline, is the present state of our knowledge of the botany of Antarctic regions, and it will be seen that by far the greater part is due to the labours of the expeditions of the last ten years. Of course such a survey as this must necessarily be incomplete, as several important papers on recent collections still remain to be published, and even when this is done our botanical knowledge of the Antarctic will have many gaps : further collections are much to be desired, especially from the Pacific and Indian sides, whence practically nothing is known, beyond of course the collections of the BeJgica, Frangais, and Pourquoi Pas? on the west of Graham Land, and the various collections from Victoria Land. Among the Antarctic lands from which no plants are known are Coats Land, Enderby and Kemp Lands, Termination Laud (if this long-lost land is identical with Drygalski's reported " high laud "), Wilkes Laud, Edward Land, Charcot Land, and Alexander Land — not to omit New South Greenland if that great peninsula really exists in the Weddell Sea — though it is quite to be expected that their flora is very scanty since they are more or less covered with ice and little bare rock appears. The explorations of the Aurora in Wilkes Land, the Deutscldand in Coats Land, and the Fram in Edward Land should add to our knowledge of Antarctic botany. While our knowledge of Antarctic flora is certainly incomplete, all the known facts point to a Fuegian origin. Not only does an analysis of the distribution of the constituent elements indicate this, but the relative greater abundance of species in Graham Land and vicinity than in Victoria Land, as well as the absence of New Zealand forms, shows that the flora of the Antarctic is due to an emigration of species from Fuegian lands. I have discussed above (pp. 6 and 7) the ways in which seeds might cross Drake Strait. Winds and birds must have done the work of giving Antarctica its present flora, via Graham Land from Fuegia, and thence it must have spread westward via the coasts to Victoria Land, but naturally only a small proportion • of the species were carried so far. However, it is quite possible that by the same agencies a certain number of mosses and lichens may have reached Wilkes Laud and Wilhelm Land from Kerguelen and Heard Island, while South Georgia and the South Sandwich group may THE PROBLEMS OF ANTARCTIC PLANT LIFE. 15 have contributed to Coats Land and the coast eastward towards Enderby Land. The floras of all these sub-antarctic islands from the Falklands eastward to Kerguelen have been shown to be related to one another, and to have strong Fuegian affinities ; and Dr Cockayne has pointed out the relationship between the flora of Kerguelen and that of Macquarie Island. In a later part of this paper (pp. 17-20) is a fuller discussion of these islands and their floras ; but this close relationship with Fuegia that they all exhibit, means that emigration of a species from any of these islands to Antarctica amounts to emigration from Fuegia by a somewhat circuitous route. No other lands are near enough to Antarctica" to have affected its flora. In relation to the flora of South Georgia, Dr Skottsberg has discussed at some length the probability of wind and bird carriage of various species : reference should be made to that paper.1 Taking into account our incomplete knowledge of the Antarctic flora, the total number of species which occur in Antarctica may seem large when all must have been brought by such chance agencies as wind and birds ; yet I believe that the existing species in Antarctic regions represent a small proportion of those that have reached there. The probability of seeds and spores reaching a location suitable for growth is small, and even then only specially favoured species could survive the adverse conditions of life with which they have to contend. The high proportion of endemic species among the mosses in particular is, of course, the outcome of this most specialised environment. One element of the Antarctic flora may appear to present a difficulty in the way of the acceptance of this theory — that is, the northern element. Dr Cardot has found a large proportion of these forms among the mosses of both Antarctic and sub-antarctic regions. But their presence can be satisfactorily explained, and that without recourse to the now discredited theory of bipolarity. Dr Cardot suggests2 that the spores and soredia of these mosses and lichens may be transported on the feet and plumage of those birds which we now know wander between high northern and high southern latitudes. Wilson's petrel (Oceanites oceanicus), which breeds in the Arctic regions, was found by us during the northern winter off Coats Land ; the northern tern (Sterna macrura) was proved by the naturalists of the Scotia to wander almost from pole to pole ; and other species of birds might be cited that range between Alaska and Fuegia. While there may be some degree of probability in Dr Cardot's theory, I do not feel it gives an adequate explanation of the facts, and I think that a more satis- factory and simpler explanation is to be found in the idea that the species of mosses and lichens in question are either cosmopolitan, but have not been discovered in low latitudes, or that they are species which have spread from northern to southern regions (or vice versa) by means of mountain ranges or bird and wind transport, but which 1 "Die Gefasspflanzen Sudgeorgiens," Carl Skoltsberg, Wissen. Erg. Schwed. Siidpulur-Ej-ji., iv. 3. 2 " Note sur la Flore de 1'Antarctide," Jules Cardot, Comptes rendus de VAssoc. Fran^aisepour Favancement des Sciences, 1907, pp. 452-460. 16 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. have failed to prosper iu low latitudes either by inability to become adapted to the physical conditions, or by stress of competition. Although the foregoing explanation seems to solve the problem of the origin of the Antarctic flora, it may be as well to examine other solutions which have been put forward. It has been suggested that the present flora represents the relics of a richer flora from pre-glacial days, which doubtless reached Antarctica by land connections with America and Australia. The existence of these land connections has certainly been established beyond doubt by the work of the Belgica, Scotia, Antarctic, Nimrod, and other expeditious ; yet, for reasons that I will explain, it is doubtful if they can help to answer the question of the origin of the flora. In every part of Antarctic regions explored by recent expeditious proofs of a former great extension of glaciation have been found, and this at a date posterior to those late Secondary and early Tertiary land connections. M. Arctowski of the Belgica showed that Gerlache Strait was once filled by an immense glacier. Dr Gunnar Andersson speaks of an island (Moose Island) in the same strait over 600 feet, rising from over 600 fathoms depths of water, which shows indisputable signs of ice-action on the top. At Borchgrevinck Nunatak, in 66° S. in Graham Land, it was found by Dr Otto Nordenskjold that the ice-sheet formerly was about 1000 feet above its present level.1 According to the German Antarctic Expedition the ice-sheet of Wilhelm Laud, which is now some 900 feet thick, was at one time 1300 feet. The South Orkneys show similar traces of this greater glaciation in the past, and Captain Scott noted it in Victoria Land. Messrs David and Priestley of the Nimrod believe that McMurdo Sound was once filled with a branch of the Ross Barrier, whose general surface was then 1000 feet above sea-level, in contrast to 150 feet to-day. And many other instances could be cited. Under these conditions of glaciation little if any land can have been exposed, unless it was a mere mountain top or cliff side.2 Moreover, there are not wanting signs that after this period of maximum glaciation the land rose. Dr Gunnar Andersson found signs of emergence of the land at several localities in Graham Land visited by the Swedish Antarctic Expedition. Messrs David and Priestley suggest emergence of the laud as an explanation of the raised beaches of Victoria Land.3 From all the available evidence they conclude that the land has emerged possibly as much as 130 feet. Now, if this was the case, and there was depression of the land during the extreme glacial period — perhaps due to the enormous superincumbent weight — the great majority of the low-lying places near the sea, including many small islands, which at present harbour the flora of Antarctica, must have been below water, while all those more elevated places of to-day which now bear vegetation were enveloped in ice. The 1 "On the Geology of Graham Land," J. G. Andersson, Bull. Geol. Instit., Upsala, vii., 1906, pp. 19-71. 2 It should, however, be noted that Dr 0. Nordenskjold holds a contrary opinion, believing that the maximum glaciation did not cover all the land with ice. Geog. Journ., Sept. 1911. While recognising the high authority of the writer, I must confess to be unable to agree with him. 3 The Heart of the Antarctic, E. H. Shackleton, London, 1909, vol. ii. p. 271. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 17 present loci for the scanty Hora of Antarctica can only have become such when glaciation had for some time diminished. It is difficult to believe that any species, unless possibly a lichen or two, can be a survivor of an older Antarctic flora. At the period of severest glaciation the sub-antarctic islands were heavily glaciated —of that we have proof in many cases — but probably not to such an extent as to exterminate any pre-existing flora, only greatly to diminish it, though there are indica- tions that in South Georgia and Macquarie Island the flora was wiped out. Turning now from the true Antarctic regions to the austral or sub-antarctic regions, consisting mainly of the many islands that gird the Antarctic seas, it must be said that it is here that the most fruitful botanical collections of future expeditions will probably be made. This ring of circum- polar islands includes the following : — Fuegia, the Falk- lands, South Georgia, South Sandwich group, Tristan da Cunha with Gough Island, Bouvet Island, Prince Edward and Marion Islands, the Crozets including Possession Island, Kerguelen, Macdonald and Heard Islands, St Paul and Amsterdam, Campbell and Auckland Islands, Macquarie Island, and Dougherty 1 or Keates Island, with a few others whose existence is somewhat hypothetical. In passing it may be as well to note that I have included all these islands in the general category of sub-antarctic merely for the sake of convenience in this place, and do not intend to imply that on botanical grounds they can be grouped in the same domain : for a discussion of the classification of these islands reference should be made toDr Skottsberg's paper (loc. cit.). Of these islands Fuegia and adjoining Patagonia, as well as the Falklands, have been well studied by various expeditious, including the recent most fruitful one led by Dr Skottsberg ; South Georgia has been recently re-explored by the Swedish Antarctic Expedition ; Tristan da Cunha has hardly been exhausted despite the visit of the Challenger ; Gough Island, on which 1 had the privilege of being the first botanist to land, would well repay a visit ; Prince Edward and Marion Islands, the Crozets, Kerguelen, Macdonald and Heard Islands, are far from well known, except perhaps Kerguelen ; St Paul and Amsterdam Islands are better known, and the New Zealand group, includ- ing Campbell, Auckland, and Macquarie Islands, and the Antipodes, have lately received more attention. But all would be worth the attention of a careful explorer, especially as regards the lower forms of plant life. Bouvet and Dougherty Islands are altogether unknown from a botanical or almost any other standpoint. Bouvet Island, according to the Vctldivias reports, is entirely covered with ice, and is devoid of vegetation : moreover it offers no landing-place. On the other hand, previous voyagers have given the island a slightly better reputation, Bouvet (1739) and Lindsay (1808) both reporting trees and shrubs (? tussock grass), and Morrell (1823) speaking of small spots of vegetation. Whatever may be the case it well 1 The Discovery reported that this island does not exist in its formerly assigned position, and Captain J. K. Davis of the Nimrod cast grave doubts on the existence of Emerald Island and the Royal Company Islands as well as Dougherty Island. VOL. Ill 3 18 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. merits a visit, and in view of its probable accessibility at all times of the year, even in an iron vessel, it is to be hoped it will not be long before we have some definite knowledge of the natural history of the island and its surrounding waters. Gough Island, I can assure any intending botanical explorer, will more than repay a visit, and it is not difficult of access, though landing may be a little troublesome.1 Many important botanical discoveries could be relied on. The six islands lying in the extreme South Atlantic, which were discovered and named by Cook in 1775 the South Sandwich group, are probably the most neglected spot in all sub-antarctic regions, and no expedition since that of Bellingshausen in 1820, with the ships Wostok and Mirny, has visited them, though several sealers and whalers report that they are quite accessible and contain some good harbours, especially one on Bristol Island. Forster, the German naturalist who accompanied Cook, says no vegetation was to be seen, though Cook himself mentions that he observed vegetation to the north end of Saunders Island. Morrell in his somewhat doubtful voyage of 1823, speaking of the islands, says they are " entirely barren." The Scotia, on her first Antarctic voyage in 1903, passed within twenty miles of Southern Thule, the southern- most island of the group, but thick and boisterous weather prevented a nearer approach and time was too precious for the southern cruise to admit of delay : on our return from Coats Land in 1904 an attempt was made to reach the group, but continual adverse gales and a shortage of coal caused the project to be abandoned. Nothing therefore is really known of this group, and a large field is open for some future explorer.2 It is to be hoped that the Deutschland will succeed in her contemplated exploration of this group. Probably it will be found that all the islands of the group are not barren of vegetation, while their extreme interest from a botanical point of view lies in their position intermediate between Antarctic and sub-antarctic zones, the southern- most islands approximating to the Antarctic conditions, though doubtless not quite so rigorous, and the northernmost islands no doubt having a climate somewhat similar to that of South Georgia, or perhaps a little more severe. In this chain of islands extend- ing through three degrees of latitude, one should be able to study the gradual transition from sub-antarctic to Antarctic flora in a way which no other part of the south polar regions permits. There is every reason, therefore, to expect that the vegetation of the northern islands will approximate to that of South Georgia, and that of the southern islands, at least Thule and Bristol Islands, will show some similarity to the true Antarctic facies. The floral statistics should also prove of great interest, and may throw some light on the vexed question of the origin of southern floras and former land connections. The flora, especially of Traversey and Candlemas Islands, will probably show a distinct South Georgian and consequently South American relationship, but 1 " Diego Alvarez, or Gough Island," R. N. Rudmose Brown, Scot. Oeog. Mag., xxi. p. 430 et scq. - An account of some zoological collections made at the Sandwich group by Captain Larsen and Dr F. Lahille of Buenos Aires has recently appeared (Ann. de Mus. Nac. de Hist. Nat., ser. iii. vol. xiv.), but at the time of going to press I have not heard whether this expedition had any botanical results. The Deutschland in November 1911 was said to have visited this group of islands. THE PROBLEMS OF ANTARCTIC PLANT LIFE. 19 the point of extreme interest to be looked for is whether it will show near relationships to the flora of the Crozets on the one hand, or to that of the Tristan da Cunha group on the other, and it will be interesting to find out how far this Sandwich group flora has evolved, and whether any new and distinct species have originated. The flora of South Georgia has practically no relationship to that of Tristan da Cunha or Gough Island, but a certain affinity with that of the Crozets and other islands to the east, and with the Antarctic regions properly speaking : of its 93 species of mosses, 16 are also found in the Antarctic. Its Magellan affinities are more pronounced : indeed, it seems probable, as Dr Skottsberg maintains (loc. cif.), that the flora is derived entirely from Fuegia and the Falklands ; no species, he asserts, shows any other origin. Yet considering its nearness to Fuegia, and the prevailing westerly winds, it is a matter for wonder that more of the Fuegian species are not found there, and that the proportion of endemic species should be so high in respect of mosses, viz. over 45 per cent., according to Dr Cardot's determinations. Among its 15 species of phanerogams are none which are endemic, a fact not a little remarkable considering how, in similarly isolated islands, such as Tristan da Cuuha and Gough Island, the endemic species and varieties form a conspicuous element of the flora, while Kerguelen and other islands to the east are also not wanting in this respect. Possibly the relative accessibility of South Georgia to the Magellan Lands accounts for its want of peculiar species ; but if this is so, the number of endemic mosses does not become easier of comprehension, nor the paucity of phanerogams, since there are other Fuegian and Falkland species quite suitable for South Georgian conditions and adapted for wind and bird transpersion. The affinities of the flora of the New Zealand group of sub-antarctic islands with that of Fuegia, which Dr L. Cockayne and others have demonstrated, and to which reference was made above, is another striking fact. Recent exploration undertaken by the New Zealand Government has added much to our former knowledge of these islands.1 The whole flora of the Snares, the Aucklands, Campbell Island, the Antipodes, and Macquarie Island, contains, as far as our present knowledge goes, 194 species of flowering plants, among which there is a NewT Zealand element of 133 species, an endemic one of 53 species, and a Fuegian -South -Georgian -Kerguelen element of 8 species unknown in New Zealand. The New Zealand species are probably of com- paratively recent introduction, and reached the islands since they were separated from New Zealand. The endemic element shows in some cases New Zealand affinities, in others none at all. The first part was no doubt derived from New Zealand in the long- past ; the second part represents the relics of some older pre-glacial flora. The Fuegian element has been introduced by wind and bird transport : with so small a percentage of species this is quite likely. On the other hand, out of the 88 genera of phanerogams in these islands, no less than 56 have representatives in Fuegia. This obviously points to some most intimate link between the floras of these islands and that of Fuegia in the 1 The Sub-antarctic Islands of New Zcalm/i!, C. Chilton, L. Cockayne, T. F. Cheesem.in, and others, Christchurcli, N.Z.. I: 20 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. past. Such a link could only have been made by land connections, and it was probably at the time of the last stages of the former wide northward extension of Antarctica that this deep-seated affinity between these floras must be dated. To name an epoch for this would be rash : possibly these land bridges were available as late as Eocene times. After they were no longer in existence, the floras of the various islands developed each along its own lines, and the endemic species were evolved. The only later addi- tions were by wind and bird transport from Fuegia and from New Zealand. A full discussion of the relationships of the floras of these southern islands in their possible bearing on the former distribution of land has great importance, but is out- side the purpose of the present paper. Enough has been said to indicate the nature of the botanical problems awaiting solution in Antarctic and sub-antarctic lands, and while future expeditions will naturally choose their routes largely for oceanographical and geographical reasons, there always will be in any land touched at, or for that matter in any sea, sufficient material of botanical interest to be found. The pole-circling islands and the coasts of Antarctica are more likely to be well explored as the importance of the study of the vast southern oceans begins to attract the attention it deserves, and when the day of record-breaking pole-hunts is over, as it soon must be now that Roald Amundsen has won the race. The present Australasian expedition with no pole-reaching ambitions is a welcome sign of the trend of exploration. SCOT. NAT. ANT. EXP. VOL. III. CHART TO SHOW THE DISTRIBUTION OF LAND IN ANTARCTIC & SUB-ANTARCTIC REGIONS BOTANICAL RESULTS. .Ttismii tin t'uutui .'..,.. A /_ MI-..MJI : ±. r"'"up nlwirJi ,1 Mil,. - Suulb '; Y, "•"^ , Strrtun t .-^ -> ^ . • \ a is \ 1 l.TtM .1.1 Soil III o ».- \]r-,fSolHV ) I'nwhrrrj nr~Eealx*L°* o s S E 4 '-r.l,. ' ) s.ii^iiM 5 3 ^Inttpfttfe" r' f^tmtv /- Em^-aU.L ' '• ,Ui JC*^ NEW /f*. ./ZEALAND * j^oyol&mpaayZ, "^N TASMANIA' : A LartffitucU West 15O of^ (,rfrr>*-i,Jt , o (i-11/.rt PwnitiaiX* 1'lwids K.T^urli- 'llfl.-!! I ^ ^* ,V /',.„„'.// J ffft,uJ7. ^ A T^-S T/ft A\L I As 160 f.ontpitude £ayt IjO o^1 Grtenwich II.- THE BOTANY OF THE SOUTH ORKNEYS, II.-THE BOTANY OF THE SOUTH ORKNEYS.1 By R. N. RUDMOSE BROWN, D.Sc., and 0. V. DARBISHIRE, B.A., Ph.D. (\Vith a Plate.} I. INTRODUCTORY. By R. N. RUDMOSE BROWN, D.Sc. THE small group of islands known as the South Orkneys is situated between 60° and 61° S. and 44° and 47° W., about 600 miles S.E. by E. of the Falkland Islands, and about 200 miles east of the nearest islands of the South Shetlands. They were discovered in 1821 by Powell in the sloop Dove, and were subsequently visited by Weddell in the brigs Jane and Beaufoy in 1823, by Dumout d'Urville in the Astrolabe in 1838, and by Larsen in the whaler Jason in 1893. In February 1903 the Scottish National Antarctic Expedition in the ship Scotia made a landing on Saddle Island — the most northerly island of the group — on their way to the south. In the end of March the same year the Scotia returned to the islands to winter, and spent eight months at Laurie Island. The group consists of two large islands — Coronation and Laurie Island, and many smaller ones. Coronation Island, or Mainland, is the westerly, and Laurie Island the easterly. It was on the latter island, in the south of which is Scotia Bay, that the greater part of the botanical collections were made. These two islands are separated from one another by two small islands and Washington and Leathwaite Straits. Of the outlying islands the most important is Saddle Island, lying about eight miles north of Laurie Island. Ailsa Craig, mentioned several times in this paper, is a large rocky crag standing at the mouth of Scotia Buy. Deep bays run into the land from north and south, separated by narrow rocky peninsulas or steep and lofty mountain ranges. All the valleys are choked with glaciers, despite the relatively small gathering-ground on the heights above, and what little exposed rock is visible is precipitous in the extreme. It is only here and there that a few acres of more or less level ground are to be found on the lower slopes or at sea-level. Although in a comparatively low southern latitude, the South Orkneys are sometimes ice-bound for some six to eight months of the year. In other years they may enjoy more oceanic conditions and escape this extreme rigour. In midwinter practically everything, even to the faces of precipitous cliffs, is covered with snow, and 1 Reprinted with alterations and corrections from Trams, and 1'roc. Bot. Soc. Edin., xxiii. i., 1905, pp. 105-110. 23 24 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. not before October or November does much of the snow disappear. In these months many patches of moss-covered ground come to light, and in some of them, by successive years' growth, 6 to 10 inches of soil have been formed. Except this vegetable mould, there is little soil anywhere. The rocks — various kinds of greywacke — are mostly covered with lichens, particularly Usnea and Placodium, and Weddell,1 to whom we are indebted for the first account of the islands, mentions that at Cape Dundas, where he landed, " there was a patch of short ' grass.' ' During the winter and spring that the Scottish National Antarctic Expedition spent at the South Orkneys, I made a very careful search for this grass both at Cape Dundas and elsewhere, but failed to find any signs of it. It is possible that this grass may have been casually introduced, and succumbed after a few seasons to the severity of the climate, or been unable to grow on account of the numbers of penguins that frequent the place, yet I am inclined to think Weddell mistook a lichen ( Usnea melaxantha), growing luxuriantly at Cape Dundas, for a grass. This was also the impression of Duinont d'Urville, who visited the island in 1838.2 Cape Dundas, it must be remembered, is the easternmost point of the islands, and therefore the least likely spot for wind-carried seeds to be deposited in that region of the westerly winds ; and the coast there is unprotected and the anchorage bad, which make it improbable that whalers who could have been responsible for the introduction of the plant would have landed there, unless, like Weddell, they had a scientific end in view. However, it is worth noting that the South Shetlands and Graham Laud, which are very similar in physical conditions to the South Orkneys, support Deschampsia antarctica, and Graham Laud Colobauthus crassifolius. Owing to the fact that the South Orkneys lie within the region normally ice-bound in winter, the temperature is comparatively low, ranging from a mean of 97° F. in midwinter (July) to 31 '5° F. in midsummer (January). The extreme range is from —40° F. to 47 '8° F., but an approach to either of these extremes, particularly the latter, is rare. The mean of the year is 23'36° F.3 Snowfall is great, sunshine very deficient, and strong gales frequent. The mosses of the South Orkneys are considered in Dr Cardot's paper, on pp. 55-57 of this volume. II. THE LICHENS OF THE SOUTH ORKNEYS. By OTTO V. DARBISHIRE, B.A., Ph.D. The lichens of the Arctic regions are fairly well known, and for this state of things there are three reasons. The limits of the Arctic regions are well defined ; further- more, a very large amount of material has at various times been brought back to Europe ; and, lastly, this material has been worked through critically and as a whole by various lichenologists. 1 A Voyage toward the South Pole in the years 1S22-24, James Weddell, London, 1825, p. 24. 2 Voyage du P6le Sud, Dumont d'Urville, Paris, 1841-45, vol. ii. p. 131. 3 Subsequent data will slightly alter these values, but probably not more than a fraction of a degree. The values here given are the means for five years. THE BOTANY OF THE SOUTH ORKNEYS. 25 With regard to the Antarctic lichens, on the other hand, we have three difficulties to contend with. The limits of the Antarctic regions do not admit of easy definition. We have, secondly, no very extensive and exhaustive collections from certain limited areas, but rather a sample taken here and a sample taken there, in localities to which often flying visits ouly have been paid by expeditions. This becomes the case more and more the farther south we go. Of course the scattered nature of the land, which may be included in the term Antarctic, is largely responsible for this being the case. Lastly, we are still in want of a critical examination of all the herbarium material that has so far been collected, and all that there is to be found in the literature. There must be a sufficiently great quantity of material in European an'd American herbaria, and in the literature of the subject, to make such a critical examination a fairly hopeful under- taking. But a compilation of the printed records must be accompanied by a critical examination of the corresponding herbarium specimens. Till this herculean task has been successfully accomplished we must confine our energies to getting hold of every possible morsel of lichen material from the Antarctic regions and carefully recording name and locality. From this point of view the lichens brought back by the Scottish National Antarctic Expedition, and collected by Mr R. N. Rudmose Brown, are very interesting and valuable. Eleven species were collected at the South Orkneys. I will now enumerate the species, adding any observations that may appear necessary, and then make some more general remarks on the distribution of Antarctic lichens. LECIDEA FUSCO-ATRA (L.), Tli. Fr. — Occurs in the Arctic regions. South Orkneys. RHIZOCARPON GEOGRAPHICUM (L.), D.C. — Found on rocks in Scotia Bay, South Orkneys. It is a cosmopolitan species, being frequently met with in the Arctic regions, and it may also be described as being a typical Alpine plant. GYROPHORA VELLEA (L.], Ach. (or VELLEREA (L.), Ach,, according to Arnold) was collected on rocks on the south-west shore of Scotia Bay rising to a height of 1000 feet. It was also collected on Saddle Island at a height of 300 feet. The specimens were all well developed, one measuring as much as 11 by 20 cm. The latter was found growing in close association with Usnea melaxantha, Ach., some plants of which were actually firmly attached to the surface of the Gyrophora plant. Gyrophora vellea is recorded from America and Europe, being an Arctic and Alpine plant. CLADONIA FIMBRIATA (L.), Fr. — This species, though otherwise cosmopolitan in distribution, does not occur in the extreme Arctic regions, and its discovery in the South Orkneys, where it was found between moss in Scotia Bay, is of great interest. CLADONIA DEFORMIS (Ach.), Hffni. — A few specimens of a Cladonia brought from Scotia Bay, South Orkneys, seem to belong to this species. It is again cosmopolitan, being also a typical Arctic and Alpine plant. VOL. III. 26 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. USNEA MELAXANTHA, Ach., is common both in the Arctic and Antarctic regions of America and Europe, and also in New Zealand and the Andes. A number of species appear to be nearly related to this plant, but they are not all quite clearly defined. I am referring to U. Taylori (Hook.) ; U. Hieronymi, Krphbr. ; U. trachycarpa, Miill.- Arg. ; and even U. sulphurea, Konig, which is probably only a synonym of U. indax- antha, Ach. Some of the specimens were found growing on and firmly attached to Gyrophora rellea. BRYOPOGON .TUBATUM, Link. — Cosmopolitan, Arctic, and typically Alpine. Small plants were found in between specimens of Usnca melaxantha from the South Orkneys. RINODINA TURFACEA ( Wahlenb.), Fr. — Europe, Asia, and America, Alpine and Arctic. The material collected from a rock on the South Orkneys must, I think, be included in this species. It has a remarkably well-developed, thick thallus, but this may be due to its unusual habitat on rocks. PLACODIUM ELEGANS (Ach.}, Nyl. — Cosmopolitan, Arctic, and typically Alpine. Good fertile specimens were found on rocks on the south-west shore of Scotia Bay, South Orkneys. PLACODIUM REGALE, Wainio ( = Placodium fruticulosum, Darbish., Trans, and Proc. Bot. Soc. Edin., xxiii. 1. (1905) J). --Thallus fruticulosus, basi substrate affixus. Protothallus gonidiis destitutus, chondroideus, margo effusus et hyphis instructus solitariis vel conglutinatis. Podetia fruticulosa, ad marginem thalli prostrata et leviter compressa, inferne albida, nondum substrate affixa nisi protothallo ; ad centrum thalli erecta, 1-2 cm. alta, dichotome sed irregular! ter divisa, 1-1 '5 mm. crassa, ad apices bene divisa; apices juxtapositi thallum crustaceum simulantes; aurantiaca aut flaves- centia, KHO purpurascentia ; stratum corticale hyphis instructum transversalibus, cuticulo valde distincto obtectum 6-8 M lato ; stratum medullare dense strupeum. Gonidia protococcoidea. Apothecia lecanorina, 1-4 mm. lata, emergentia, sed adpressa, lateralia ; amphithccium distiuctum, gonidiis instructum; parathecium decoloratum; epithecium flavescens aut aurantiacum, KHO purpurascens ; hypothecium decoloratum, strato gouidiali inferne instructum; thecium 90-100 M crassum ; paraphyses simplices, apice cellulis brevibus terminantes ; axi cylindrici, elevati 10 fj- lati ; sporse octonse hyalinse bicellulares orculiformes, 5-6xlT5 n magnse. Spermogonia et soralia uon visa. Habitat ad saxa, S. Orkneys. Placodium regale was found growing on rocks around Scotia Bay, South Orkneys. It is apparently very common from the shore right up to the summit, evidently repre- senting an important constituent of the lichen vegetation. The podetia are fruticulose and erect, branching frequently and in an irregular way. The tips of the branches, however, are pretty much of the same height, and being very closely applied to one 1 This species was described independently by M. Wainio and Dr Darbisliire from the Belyica and Scotia collections. — R. N. R. B. THE BOTANY OF THE SOUTH ORKNEYS. 27 another, this lichen appears to be crustaceous. The exposed parts of the plant are light yellow or orange coloured, hut those more hidden are paler, and in part even white. The lowest portions of the podetia can obtain a thickness of about 1'5 ram., the tips being as much as 1 mm. across. The podetia measure up to 2 cm. in height, and are generally cylindrical in section near the margin. Near the margin of the whole thallus they generally assume a more typical Placodium structure. The marginal podetia show a dorsi-ventral arrangement, the short assimilators springing from the upper side only. But even here, near the margin, the dorsiventral and free podetia can lie distinguished perfectly from the protothallus, which is firmly attached to the rocky substratum. The protothallus consists of fine strands of fungal hyphse, which, white in colour, radiate out in an irregular manner from the base of the podetia. At this latter point the protothallus is often very thick. The gouidia are fairly evenly distributed in the podetia, where these are exposed to light, but the gonidia are massed together at those points where a new branch or an assimilator is about to sprout. The general structure of the apotheciuni is that typical of Placodium species. It is up to 4 mm. in diameter, with orange epithecium and distinct thalline margin, which, however, gradually sinks below the level of the epithecium. The light hyaline spores are polar-bilocular ; parathecium and amphithecium are colourless, and green gonidia are found under the hypothecium. This plant is very nearly related to Placodium coralloides, Tuck. (Synopsis of the North American Lichens, i. p. 169), and P. dadodes, Tuck. (foe. cit.). It differs from the latter by having colourless spores in each ascus instead of one brown one. It is also stouter and bigger than both species of Tuckerman. I have only seen specimens of P. coralloides. The big apothecia of P. regale also retain their amphithecium through- out life. Placodium regale is an interesting plant which belongs to the subgenus Thamnoma of Placodium, created by Tuckermau for his species coralloides and cladodes. The thallus is throughout distinctly diploblastic, the protothallus being easily separated from the podetia, even when the latter are prostrate, near the margin of the plants. Several species of Placodium have a tendency to become fruticulose. Thus in H. Lojka Lich. Regni Hung, exsic. i. (1882), n. 26, Lccanora elegai/s Lk. v. compacta (Arn.) Nyl. ( = Placodium) shows fruticulose podetia in the centre of the thallus. XANTHORIA LYCHNEA (Ach.), Th. Fr., North and South America, North Asia and Europe. A number of small plants were found between some podetia of Placodium regale. Rocks in Scotia Bay, South Orkneys. Some fragments of crustaceous lichen are amongst the material brought from the South Orkneys, which, however, it is impossible to identify at present. But disregarding these, we have before us, brought back by the Scottish National 28 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Antarctic Expedition, 11 species from the South Orkneys. It is difficult with these few specimens to draw any conclusions, but it is interesting to note that all except Placodium regale are found in the Arctic regions, and 5 are more or less Alpine. In a paper on the Greenland lichens collected by Vauhoffen (BM. Hot., No. 42, 1897), the author of the present paper mentions that of the 286 known Greenland species, 213 were found also in Germany. Of these latter 105 (i.e. 49'4 per cent.) are purely Alpine species, 11 (5'1 per cent.) prefer Alpine conditions, and 97 (45'5 per cent.) are equally at home on the hills and in the plains. That is to say, 54'5 per cent, are typical hill species, and none of the Greenland lichens found in Germany are confined to the lowlands. The lichen vegetation of the former very closely corresponds, therefore, to the German Alpine flora. We have not enough material to make such a complete comparison of the Antarctic lichens, but I would like to give some statistics attempted with the lichens brought back by H.M. discovery ships Erebus and Terror in the years 1839-43. These number about 124, and 44 are apparently extra-European. But of the remaining 80 species, which also occur in Europe, 2*5 per cent, are typical lowland plants, 23'75 per cent, typical Alpine plants, 66'25 percent, are found on hillside and in lowland equally, 7'5 per cent, are exclusively Arctic, but of all the Antarctic and European species 73'75 per cent, occur also in the Arctic regions. Even the small material before us therefore admits of some interesting reflections on the great similarity between the Arctic, Alpine, and Antarctic regions in their lichen vegetation. We can imagine the ancient polar floras having been continuous at one period, and then, with the decrease in the cold of the climate, the lichens followed the retreating ice and snow into the hills and the Arctic and Antarctic regions. We find further evidence for this when we compare the most highly developed and therefore oldest lichens with the lower and therefore more recent forms, in regard to their distribution in the Arctic and Alpine zones. Of the Greenland fruticulose lichens 5'5 per cent, alone are unknown in Germany, of the foliose forms 14'3 per cent., and of the lower crustaceous forms as many as 3 5 '6 per cent. But no special notice is taken of those species which occur in the regions lying between Greenland and the German Alps. A still more interesting comparison could be made by comparing the Antarctic lichens of America with the Alpine forms of the same continent and the Arctic lichens, but as yet the material at our immediate disposal makes this impossible. These few remarks do favour the view that a very close relationship does exist between the Arctic and Antarctic lichens, which, however, must date back to the time when they were still constituents of one flora. It will be seen from this that further collections of Antarctic lichens would be of very great interest. SCOT. NAT. ANT. EXP. DARBISHIRE: SOUTH ORKNEY LICHENS — PLATE I. VOL. III. . ^^ 2. 0 V Darbi shire del PLACODIUM REGALE, Wainio. TILE BOTANY OF THE SOUTH ORKNEYS. 29 EXPLANATION OF THE PLATE. P/(ii-/i/lii/ii/ ref/ale, Wainio. Fig. 1. An upright podetium showing the small knob-like assiinilators, which, at the top, <; form the roof, whirli gives this lichen a crustaceous appearance, a, substratum; 1>, protothallus ; c, top of P'ulrtiuin. x 8. '2. Longitudinal section of a similar poiletium, showing the distribution of the gonidia, g, in the rounded projecting assimilatnrs. in, medullary, c, cortical portion, artina anmdinacea) was not, at the place of landing, so abundant as in other parts of the coast, but here and there on the hillsides down to the sea-level there were large tufts of it. In habit it is very similar to the tussock-grass of the Falkland Islands, but does not appear to grow in such masses as almost entirely to exclude other plants as it does on those islands. The only sward-forming " grass " seems to be Scirpus (spp.) : on the southern side of the stream was about half an acre of this, making a rich pasture. Other grasses are to be found, but growing in more isolated tufts. The characteristic tree of the Tristan da Cunha group (Phylica nitida) is well represented, and grows on Gough Island from about 2000 feet to sea-level, but above 1 00 feet it is most plentiful. The tree grows some 20 or 30 feet in height even on the most exposed ridges. The stems are not very thick, not more than 10 to 12 inches, and the branches are long and straggling, with leaves only at the extreme ends. Most 1 For a fuller account of Gough Island see "Diego Alvarez, or Gough Island," R. N. Rudmose Brown, Scot. Geog. Mag., xxi., 1905, pp. 430-440. THE BOTANY OF GOUGH ISLAND. 35 of the branches are thickly encrusted with lichens. Tree-ferns grow in the rich ground beside the stream, and reach a height of 4 feet or more. The beach is thickly strewn with water-worn sterns of these ferns, which have probably been brought down by the stream when in spate, carried into the sea, and washed up on to the beach. Several species of ferns grow in nooks and crannies of the moist rocks, and apparently obtain an easy footing in the relatively soft volcanic ash. Mosses are plentiful every- where, and in the bed of the stream I "got several specimens of a liver- wort. The only plants in flower were Sonchus oleraceus and Apium australe and two species of Rume.c, and the majority even of these were in seed. Gnaphalimn pyra- midale bore withered flowers, and Phylica nitida and Empetrum nigrum, var. rub-rum, were in fruit in a few places. I found no trace of any plants introduced for cultivation by the settlers whose ruined huts we found. Beyond the huts was half an acre of ground beset with tree-stumps, the remains, no doubt, of the native tree which had been cut down for firewood. The phanerogams and ferns of Gough Island, as might be expected, have proved to be very similar to those of Tristan da Cunha. The present collection contains 17 species of phanerogams and 10 of ferns. Four of the 17 species of phanerogams are almost without doubt introduced (Hijpocliceris glabra, Sonchus oleraceus, Rumex obtusifolius, and Plantago major}. Of the remaining 23 species of Gough Island plants, 20 are recorded from Tristan da Cunha — one (Hydrocotyle leucocephala) is a South American plant and two are endemic (Cotula, sp. nov., and Asplenium, sp. nov.). Of the 18 species also recorded from Tristan da Cunha, four certainly, and probably six, are endemic to the group. The mosses collected by me at Gough Island comprise 21 species, of which 11 are new. A discussion of the affinities of the Gough Island flora as exhibited by the mosses is contained in Dr Cardot's paper in the present volume (pp. 57-66). Excluding the 11 endemic species and one which is only geuerically determined, but which is probably new, 9 species remain. Of these two are more or less cosmopolitan, and four others are of wide distribution in the southern hemisphere, so that their presence in Gough Island proves little from a geographical point of view. Two species occur in both Gough Island and Tristan da Cuuha, and one in Gough Island and Ascension. One would expect the relationships to Tristan da Cunha to be more marked, and I agree with Dr Cardot that further exploration will probably prove this to be the case. Otherwise the Fuegian affinities are most marked in the moss flora of Gough Island, but I do not feel that our knowledge of that flora is anything like adequate enough to justify our drawing from it any deductions of a geographical nature regarding former land connections. For though, as Dr Cardot points out, 6 of the 9 extra-Gough Island species are found in Fuegian lands, their cosmopolitan nature or wide distribution in high southern latitudes militates against their being used as evidence in this respect. Nor must it be forgotten that a species of wide distribution in high southern latitudes would most likely be found in Fuegian lands, owing to the greater land area available there than elsewhere. 36 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. In conclusion, I have to thank the authorities at Kew and the British Museum for the facilities granted me for working in their herbaria ; and Dr 0. V. Darbishire and Mr C. H. Wright for their respective shares in this paper. To the late Mr C. B. Clarke I am particularly indebted for his determination of the species of Scirpus ; and I would express my thanks to Mr A. N. Bruce, B.Sc., for the care and trouble he has taken in the drawing of the plate of Cotula goughensis. I. PHANEROGAMS. By R. N. RUDMOSE BROWN, D.Sc. DlCOTYLEDONES. PHYLIGA NITIDA, Lam. Encycl., ii. p. 77 ; D. C. Prodr., ii. p. 35 ; Hemsl. Chall. Bot., i. ii. p. 148, t. 25. P. arborea, Thou. Esq. Fl. Trist., p. 45. P. mauritiana, B»j. ex Baker, Fl. Maurit., p. 53. Very common on the island up to a height of about 2000 feet, growing even on the most exposed ridges. It seldom grows more than some 25 feet in height, and the stems are always much bent and gnarled and generally covered with a growth of lichens. Distribution. — Tristan da Cunha, Inaccessible and Nightingale Islands, Amsterdam Island, Reunion and Mauritius. HYDROCOTYLE LEUCOCEPHALA, Cham, et Schlecht. in Linnsea, i. (1826), p. 364. Common in the glen in swampy places under waterfalls. This species differs from Hydrocotyle capitata, Thouars — the Tristan da Cunha plant — in the almost total absence of hairs on the leaves and leaf-stalks, except an occasional sparse covering near the blade. Distribution. — Brazil and Paraguay. This species does not appear to have been recorded outside these two countries. APIUM AUSTRALE, Thou. Esq. Fl. Trist., p. 43 ; Hook.f. Handb. Fl. N. Zeal., p. 90 ; Hemsl. Chall. Bot., i. n. p. 149. Common on the low-lying ground down to high-water mark and growing very rankly in places. It appears to be a very variable plant, and the Gough Island variety has the leaves broadly ovate, and not linear like the specimens from Tristan da Cunha of Carmichael and Moseley. Distribution. — Tristan da Cunha and Inaccessible Island, and very generally in extra-tropical regions of the southern hemisphere. NERTERA DEPRESSA, Gaertn. Fruct., i. p. 124, t. 26 ; Hook. f. Handb. Fl. N. Zeal., p. 120; Hemsl. Chall. Bot., i. n. p. 150. Erythrodauum alsineforme, Thou. Esq. Fl. Trist., p. 42, t. 10 (Nertera). Common in the drier and more barren places. THE BOTANY OF GOUGH ISLAND. 37 Distribution. — Tristan da Cuulia and Inaccessible Island, and southern temperate regions except South Africa. NERTERA DEPRESSA, Gaertn., var. OBTUSA, Rud. Br., var. nov. A variety distinct from the normal Nertera depressa in having all its leaves obovate with no suggestion of acuteness. Among the specimens of Nertera depressa gathered on Gough Island only one plant of this variety was found. In the Kew Herbarium there is one specimen from Inaccessible Island (Moseley, Inaccessible Island, 16.8.73) of this variety. The other specimens of this plant from Tristan da Cunha belong to the typical Nertera depressa, and the variety does not appear to occur elsewhere. Distribution. — Inaccessible Island. GNAPHALIUM PYRAMIDALE, T/HIU. Esq. Fl. Trist., p. 40; D. C. Prodr., vi. p. 234; Hemsl. Chall. Bot., i. n. p. 151, t. 26. G. Thouarsii, Spreng. Si/st. Vey., iii. p. 473. Common up the glen. Distribution. — Tristan da Cuuha and Inaccessible Island. COTULA GOUGHENSIS, Rud. Br., sp. uov. (Plate IV.) Herba annua erecta vel suberecta, 25 cm. alta inferne multe ramosa ; folia sessilia fere amplexicaulia, bipinnatisecta, segmentis lanceolatis in apicem acutum rotundatis ; capitula folia non superantia, 8 mm. lata ; involucri bractese late ovatse vel fere rotuudatse, marginibus integris ; flores dimorphi exteriores $ uniserrati sine corollis, interiores cum corollis ; achenia compressa glabra. This species is quite distinct in its much blunter leaves and broad involucral bracts from the Nightingale Island species, Cotula Moseleyi. It is near Cotula coronifolia, but differs in having broad bracts and a smaller inflorescence. Cotula coronifolia is also in general a much coarser plant. The only species of Cotula near this species as regards the broad bracts is Cotula integri folia, but in other respects this is quite distinct. Endemic in Gough Island, where it is very plentiful. HYPOCHCERIS GLABRA, Linn. Sp. PL, 810; D.C. Prodr., vii. p. 90. Very probably an introduced plant here, as Mr Hemsley considers it to be in Tristan da Cunha. Distribution. — Almost cosmopolitan. SONCHUS OLERACEUS, Linn. Sp. PL, 792. Common : probably introduced. Distribution. — Tristan da Cunha and Inaccessible Island, and generally throughout temperate regions. RUMEX OBTUSIFOLIUS, Linn. Sp. PL, 335. Probably introduced. It has not been recorded previously from the Tristan da Cuuha group. Distribution. — Very widely spread in northern and southern hemispheres. 38 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. RUMEX FRUTESCENS, Thou. Esq. Fl. Trist., p. 38 ; D.C. Prodr., xiv. p. 72 ; Hemsl. Chall. Bot., i. II. p. 154, t. 30. Very common at the mouth of the glen down to high-water mark. Distribution. — Tristan da Cunha and Inaccessible Islands. EMPETRUM NIGRUM, Linn. Sp. PL, 1022; var. RUBRUM, Hemsl. Chall. Bot., i. n. p. 154. E. rubrum. Vahl, in, Willd. Sp. PL, iv. p. 713 ; Hook.f. Fl. Antarct,, ii. p. 345. E. medium, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 508. Plentiful in dryer places. Distribution. — Tristan da Cunha, Inaccessible and Nightingale Islands, and in the Falkland Islands and Tierra del Fuego. PLANTAGO MAJOR, Linn. Sp. PL, 112. Common and doubtless introduced. Distribution. — Generally throughout the northern hemisphere, and introduced widely elsewhere. MONOCOTYLEDONES.1 SCIRPUS THOUARSIANUS, Schult. Mant,, ii. (1824), pp. 84 et 538 ; Hemsl. Chall. Bot., i. ii. pp. 156-158, tt. 33 et 34. S. prolifer, Thou. Esq. FL Trist., p. 36, t. 7. S. squar- rosa, Spreng. Syst. Veg., iv. (1827), p. 28 ; Boeck. in Linnsea, xxxvi. (1869-70), p. 507. S. Thouarsianus, Schidt., var. bicolor, Hemsl. Chall. Bot., i. n. p. 156, t. 34 (8-16). S. prolifero-ramosus, Boeck. in Flora,\vm. (1875), p. 261. S. virens, Boeck. in Flora, Iviii. (1 875), p. 260 ; Hemsl. Cliall. Bot,, i. n. p. 158, t. 33 (7-12). S. pallescens, Boeck. ex Hemsl. Chall. Bot., i. n. p. 158. S. Thouarsianus, Schult., var. pallescens, Hemsl. Chall, Bot., i. n. p. 158, t. 33 (1-6). Isolepis prolifera, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 503. I. squar- rosa, Carmich., loc. cit., xii. (1818), p. 503. I. bicolor, Carmich., loc. cit., xii. (1818), p. 503; Kunth, Enum., ii. p. 216. I. acuguana, Schult, Mant,, ii. (1824), p. 532; Kunth, Enum., ii. p. 216. I. Thouarsii, A. Dietr. Syn, PL, ii. p. 109 ; Kunth, Enum., ii. p. 216. Very common. Distribution. — Tristan da Cunha, Inaccessible and Nightingale Islands. SCIRPUS SULCATUS, Thou. Esq. Fl, Trist., p. 36, t, 7; Hemsl, Chall. Bot.,\. n. p. 155 (var. Moseleyanus excL), t. 31. S. Thouarsii, Spreng. Syst, Veg., iv. (1827), p. 27. S. conspersus, Boeck. in Linnsea, xxxvi. (1869-70), p. 505, pro parte. Isolepis sulcata, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 503; Kunth, Enum., ii. p. 216. I. Carmichaeli, Dietr. Syn. PL, ii. p. 107. Not uncommon. Distribution. — Tristan da Cunha group only, unless the New Zealand plant Scirpus sulcatus var. ? /3. tristigmatosa, C. B. Clarke, MSS., can be regarded as truly belonging to this species. 1 For the determination of the species of Scirpus I am indebted to the late Mr C. B. Clarke. THE BOTANY OF GOUGH ISLAND. 39 SCIBPUS MOSELEYANUS, Boeck. in Flora, 1875, p. 262. S. sulcatus, Thou., var. Moseleyauus, Hemsl. Chall. Bot., i. n. p. 155, t. 32 (fig. 6 excl.). Only one specimen of this was gathered, but fortunately it was in fruit. The ripe fruits were previously unknown. Distribution. — Nightingale and Inaccessible Islands. SPARTINA ARUNDINACEA, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 504; Kitnth, Enum., \. p. 279 ; Hemsl Chall. Bot., i. n. p. 160, t. 25. Ponceletia arundinacea, Thou. Esq. Fl. Trist., p. 36. This is one of the predominant plants of the island, apparently growing luxuriantly everywhere up to an elevation of over 1000 feet. Distribution. — Tristan da Cunha, Inaccessible and Nightingale Islands, and St Paul and Amsterdam Islands. POA ANNUA, Linn. Sp. PI., p. 68. A few plants of this were found near the ruined huts of some sealers. It is no doubt introduced as it is on Tristan da Cunha. Distribution. — Very widely spread. II. CRYPTOGAMS. FlLICES. By R. N. RUDMOSE BROWN, D.Sc. ADIANTUM .ETHIOPICUM, Linn. Sp. PL, ed. n. p. 1560 ; Thou. Esq. Fl. Trist., p. 34 ; Hook, and Baker, Syn. Fil., p. 123 ; Hemsl. Chall. Bot., i. ir. p. 163. A. thalictroides, Willd. ex Kunze, in Linmea, x. (1836), p. 530. A. crenatum, Poir. in Lam. Encyc. SuppL, i. p. 137. A. Poiretii, Wikstr. in Kon. Vet.-Akad. Handl. Stock. (1825), p. 443. Very plentiful in the glen. This is a very variable plant, and the Gough Island plant shows several varieties. Until a satisfactory monograph of the genus appears, it seems preferable to include all the Gough Island specimens under the name of Adiantum sethiopiciim. Distribution. --Tristan da Cunha and Inaccessible Island; Central and South America (except the extreme south), South Africa, India, and New Zealand. PTERIS INCISA, Thunb. Prodr. Fl. Cap., p. 133 ; Hook, and Baker, Syn. Fil., p. 172 ; Hemsl. Chall. Bot., i. n. p. 163. P. vespertilionis 8. Carmichaeliana, Agardh, Rec. Sp. Gen. Pter., p. 80. P. vespertilionis /3, R. Br. ex Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 513. Growing in dryer places than the preceding plant ; not very common. The Tristan da Cuuha specimens of this widely spread species differ from others in 40 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. the fact that the veins of the fronds do not anastomose at all ( vide Hook, arid Baker, Syn. FiL, p. 172). The Gough Island plants belong to the same variety. Distribution. - - Tristan da Cuuha, Nightingale and Inaccessible Islands ; also tropical and temperate South America, South Africa to West Tropical Africa, and from the Himalayas to New Zealand and Polynesia. LOMARIA ALPINA, Spreng. Syst. Veg., iv. p. 62; Hook. f. Fl. Antarct., ii. p. 393, t. 150; Hook, and Baker, Syn. FiL, p. 178; Hcmsl. Chall. Bot., i. n. p. 164. L. antarctica, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 513. Acrostichum polytrichoides, Thou. Esq. Fl. Trist., p. 32, t. 2 (A. polypodoides). Polypodium Pennamarina, Poir. in Lam. Encyc., v. p. 520. Not uncommon in the glen. Distribution. — Tristan da Cunha and South America, including the Falkland Islands and Staten Island, Australia, New Zealand, Marion Island, Kerguelen, the Crozets, St Paul and Amsterdam Islands. LOMARIA BORYANA, Willd. Sp. PI., v. p. 292 ; Hook, and Baker, Syn. FiL, p. 180 ; Hemsl. Chall. Bot., i. n. p. 163. L. magellanica, Desv. in Mag. Nat. Bcrl. (1811), p. 330 ; Hook.f. Fl. Antarct., ii. p. 393. L. palmseformis, Desv. in Mem. Soc. Linn. Par., vi. (1827), p. 290. L. robusta, Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 512. Pteris palmseformis, Tliou. Esq. FL Trist., p. 30. Many specimens of this fern were found growing in marshy ground in the sheltered glen. It reaches a height of from 2 to 3 feet, but the stems almost always grow in a procumbent position. In diameter the trunk varies from 2 inches to as much as 5 or 6. The Gough Island plant belongs to the same variety as the Tristan da Cunha one, which Carmichael described as a new species (Lomaria robusta, Carmich.). It, however, only differs in having the usually naked rachis more or less densely scaly throughout, and is hardly entitled to specific rank. It must be very plentiful farther inland, as the beach is thickly strewn with waterworn stems evidently carried down by the stream from the interior and washed up again by the sea. Distribution. — Tristan da Cunha ; Tropical America to Tierra del Fuego and the Falkland Islands ; South Africa, Mauritius, Eeunion, and Madagascar. ASPLENIUM OBTUSATUM, Forst. f. Prod., p. 80 ; Hook, and Baker, Syn. FiL, p. 207. A. obliquum, Forst. f. loc. cit. ; Carmich, in Trans. Linn. Soc. Lond., xii. (1818), p. 512. A. crassum, Thou. Esq. FL Trist., p. 33. Common in the glen. This species varies a great deal, and the Gough Island plants, while agreeing with some of Moseley's plants from the Tristan da Cuuha Islands, are considerably smaller than Carmichael's specimens from the same place. Distribution. — Tristan da Cunha, Inaccessible, and Nightingale Islands. Widely distributed elsewhere. THE BOTANY OF GOUGH ISLAND. 41 ASPLENIUM ALVAREZENSE, Rud. Br., sp. nov. (Plate IV.) Horba parva, caudex brevis, paleis paucis sparsis ; stipites 1 ad 5 cm., tenues virides nudi ; frondes oblongo-deltoides bipinnatse subcoriacese ; pinnae superiores ssepe in pinnulas indistincte divisse ; pinnulae cuneatse vel late obovatae, margine exteriore rotundato ; venae pinnularum dichotomy ; sori median! liuearcs. This species is very near to Aspknium Ruta-muraria, from which it chiefly differs in having its pinnules always entire. Unfortunately none of the specimens show the sori in very good condition. Endemic on Gough Island. It is plentiful on the stems of tree-ferns (Lomaria Boryana), but not common elsewhere. POLYPODIUM AQUILINUM, Thou. Esq. Fl. Trist., p. 32 ; Hook, and Baker, Syn. Fil., p. 311 ; P. acunhianum, Carmich. fide, Hemsl. Chall. Sot., i. n. p. 167. Nephrodium aquilinum, Hemsl. Chall. Bot., loc. cit., t. 39. Common. Distribution.. — Tristan da Cunha, Nightingale and Inaccessible Islands ; Amsterdam Island (?). POLYPODIUM ATJSTRALE, Mett. Polypod., p. 36 ; Hook, and Baker, Syn. Fil., p. 322 ; Hemsl. Chall. Bot., i. n. p. 168. Grammitis australis, R. Br. Prodi: Fl. Nov. Holl., p. 146 ; Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 510. G. magellanica, Desv. Journ. Bot., iii. (1814), p. 275. Only one specimen of this was found. Distribution. — Tristan da Cunha; Tierra del Fuego, Australia, New Zealand, and Marion Island. For the determination of this species I am indebted to Mr C. H. Wright of the Royal Gardens, Kew. ASPIDIUM CAPENSE, Willd. Sp. PL, v. p. 267 ; Hook, and Baker, Syn. Fil, p. 254. A. coriaceum, Swartz, Prod. Fl. Ind. Occ., p. 133 ; Hook. Sp. Fil., iv. p. 32 ; Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 511 ; Hemsl. Chall. Bot., i. n. p. 167. Polypodium calyptratum, Thou. Esq. Fl. Trist., p. 33. Fairly common. The Gough Island specimens are larger than the Tristan da Cunha ones of Moseley, and in size approximate more to the specimen of De 1'Isle's from Amsterdam Island. Distribution. — Tristan da Cunha ; America south of Cuba, South Africa, Mascarene Islands, Amsterdam Island, Australia, and Polynesia. ACROSTICHUM CONFORMS, Swartz, Syn. Fil., pp. 10 and 192, t, 1, fig. 1 ; Carmich. in Trans. Linn. Soc. Lond., xii. (1818), p. 509 ; Hook, and Baker, Syn. Fil., p. 401 ; Hemsl. Chall. Bot., i. n. p. 169. A. laurifolium, Thou. Esq. Fl. Trist., p. 31. VOL. III. 6 . •' i i a D A o v I 42 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Varies a little in the degree of scaliness, but the Gough Island plant is identical with other specimens from Tristan da Cunha. Distribution. — Tristan da Cunha ; St Helena, and throughout the southern hemisphere. Musci. For the mosses of Gough Island see Dr Cardot's paper, pp. 57-66 of this volume. The determinations originally published in the Journal of the Linnean Society (loc. cit.) are superseded. HEPATIC^E. By C. H. WRIGHT, A.L.S. MARCHANTIA POLYMORPHA, Linn. Sp. PL, ed. n. p. 1603 ; Taylor, in Lond. Journ. Bot. (1844), p. 480; Mont, in Voy. Pole Sud, "Astrolabe," i. p. 211 ; Mitt, in Chall, Bot., i. II. p. 178 ; Steph. Sp. Hepat., i. p. 164. Distribution. — Cosmopolitan, except that it has not been recorded from the African continent ; Tristan da Cunha. JAMESONIELLA COLORATA, Spruce, in Journ. Bot., xiv. (1876), p. 202. Jungermannia colorata, Lehm. in Linnasa, iv. (1829), p. 366 ; Gottsche, Lindenb. and Nees, Syn. Hepat., p. 86 ; Mitt, in Cliall. Bot., i. u. p. 176. Distribution. — Australia, New Zealand, South Africa, Kerguelen, Tristan da Cunha, and temperate South America ; and Clarence Island, South Shetlands. LOPHOCOLEA BIDENTATA, Dumort. Recueil Obs. Jung., p. 17 ; Gottsche, Lindenb. and Nees, Syn. Hepat., p. 159. Jungermannia bidentata, Linn. Sp. PL, ed. II. p. 1598. Distribution. — Cosmopolitan ; recorded from St Helena, but not from Tristan da Cuuha. FUNGI. MERULIUS AMBIGUUS, Berk. North Amer. Fungi, n. 175; in Grevillea, i. (1872) 69. M. fugax, Rav. Fungi Car., i. p. 24 ; Sacc. Syll., vi. p. 416. Grows on the trunks of Phylica nitida. Distribution. — North America. Du Petit-Thouars * mentions 4 fungi from Tristan da Cunha, among which is a species of Merulius which, from his imperfect description, might quite well be this species. On the other hand, it is quite likely that the American sealers who used to visit Gough Island were responsible for the introduction of this North American species. — R. N. R. B. 1 Du Petit-Thouars, Description abre'ge'e cles Isles de Tristan d'Acugna et Esquisse de la Flare, etc. : Melanges de Botanique et de Voyages (1811), p. 25. TIIK BOTANY OF GOUGH ISLAND. 43 LlCHENES. By 0. V. DARBISHIRE, B.A., Ph.D. The following is an enumeration of the 7 species of lichens brought from Gough Island by the Scottish National Antarctic Expedition, and collected there by Mr R. N. Rudmose Brown in April 1904. Of the 7 species 5 are already known as being Arctic and alpine plants :— CLADONIA SQUAMOSA, Hoffm. Deutsche FL, ii. 152. Cosmopolitan, but not Arctic. This plant was found in small quantities. PARHELIA CETRATA, Acli. Syn. Mcth. Lick., 198. This species was found growing on branches of Phylica. It is most commonly met with in more temperate parts of the world, but I do not doubt that the specimens before me, though sterile, do belong to this species. PARMELIA SPH^ROSPORELLA, Muell. Arg. in Flora, Ixxiv. (1891) 378. This specimen is small and incomplete, but both in internal structure and external appearance it corresponds to the original specimen and description of J. Miiller Argoviensis. He records its occurrence in the hills of Oregon. USNEA BARBATA, Fries, Sched. Crit. Lich. Suec., 34. A number of good healthy specimens, all sterile, were brought back from Gough Island. No attempt has been made to separate out the varieties of this species. It is found in every part of the world, being common also as an Arctic plant. RAMALINA SCOPULORUM, Ach. Lich. Univ., 604. Arctic, in Europe, Asia, and America. Gathered from rocks, and in full fruit. PHYSCIA STELLARIS, Nyl. Syn., 424. Another cosmopolitan plant, but not typically alpine. A small specimen found growing with Parmelia cetrata on stems of Phylica. STICTINA FULIGINOSA, Nyl. Syn., 347. Fairly common in all continents except Asia. Only a small specimen of this plant was collected on Gough Island, and it belongs, I think, to this species. The collection also contains some fragments of a Parmelia plant, one of which might be Parmelia saxatilis, Ach., but they are too imperfect to admit of precise identification. LIST OF REFERENCES. CARMICIIAEL, Captain DUGALD. — "Some Account of the Island of Tristan da Cunha and its Natural Produc- tions," Trans. Linn. Soc. Land., vol. xii., 1818, pp. 483-513. HEMSLEY, W. BOTTING.— Report on the Voyage of H.M.S. " Challenger," 1873-76, i. n. (1885), pp. 133 et stq. 44 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION- MOSELEY, H. N. — Notes by a Naturalist on the " Challenger," London, 1879. Journ. Linn. Soc. Loud., Bot., vol. xiv., 1874, p. 377. Du PETIT-THOUARS, AUBERT. — Description abregee des Isles de Tristan d'Amgna et Esquisse de la Flore de I' Isle de Tristan d'Acugna : Melanges de Botanique et de Voyages, premier recueil, 1811. VERRILL, G. E. — -"Notes on Birds and Eggs from Islands of Gough, Kerguelen, and South Georgia," Trans- actions of the Connecticut Academy, ix., 1895, part ii. EXPLANATION OF THE PLATES. PLATE I. Vegetation on Gough Island, showing Phylica nitida and Scirpus spp. (From a photograph by W. S. Bruce.) PLATE II. Vegetation on Gough Island, showing Phylica nitida and Spartina arundinacea. Waterworn stems of Lomaria Boryana on the beach. (From a photograph by W. S. Bruce.) PLATE III. Ferns on Gough Island, showing Adiantum sethiopicum, Lomaria alpina, Acrostichum conforme, Polypodium aquilinum, and Scirpus sp. (From a photograph by W. S. Bruce.) PLATE IV. Fig. 1. Cotula goughensis, E. N. Rudmose Brown. Plant, nat. size. ,, 2. Apex of leaf, x 2. „ 3. Inflorescence, x 3. ,, 4. Inflorescence with bract. „ 5. Vertical section of inflorescence. x 6. „ 6. Outer //.r. — /, feuille caulinaire; x 13. b, c, feuilles d'un rameau divergent; x 13. d, tissu dans le liaut d'une feuille eaulinairc ; x 270. e, tissu dans la moitie superieure d'une feuille rameale, vu par la face dorsale ; x 270. /, portion d'une section transvorsale vers le milieu d'une feuille rameale ; x 270. Fig. 2. Trematodon intermixtus. — a, plantes, gr. nat. l>, c, feuilles; x 13. d, e, capsules deoperculees ; x 13. /, fragment du peristome et spores ; x 138. Fig. 3. Campi/fopus alvarezianus. — a, plante, gr. nat. b, c, d, feuilles ; x 13. e, tissu basilaire d'une feuille; x 138. /, tissu vers le milieu d'une feuille; x 270. , r, feuilles; x 13. '/, tissu de la partie superieure de la base d'une feuille; x 138. e, tissu marginal vers le milieu 'd'une feuille; x 138. /, sommet d'une feuille; x 138. Fig. 8. Thuidium alrarezianum. — a, b, plantes, gr. nat. c, extremite d'une tige ; x 13. d, e, f, feuiiles caulinaires ; x 32. g, h, i, feuilles d'un rameau primaire ; x 32. j, k, /, feuilles d'un rameau secondaire; x 32. m, tissu marginal vers le milieu d'une feuille caulinaire ; x 270. n, sommet d'une feuille caulinaire ; x 270. o, paraphylles ; x 270. Fig. 9. Isopterygium Brownii. — a, I>, c, plantes, gr. nat. d, extremite d'une tige; x 13. e, f, g, h, feuilles ; x 26. z, tissu basilaire d'une feuille ; x 270. _;', sommet d'une feuille ; x 270. Fig. 10. Isopteryyium ambiguum- — a, plante, gr. nat. b, extremite d'une tige; x 13. c, d, e, f, g, feuilles; x 13. /<, tissu basilaire d'une feuille ; x 270. i, sommet d'une feuille ; x 270. Fig. 11. Brachythecium pallid* iflavens. — a, plante, gr. nat. b, extremite1 d'un rameau ; x 13. c, d, e, feuilles; x 26. /', tissu basilaire d'une feuille ; x 270. g, tissu marginal dans la moitie superieure d'une feuille ; x 270. li, sommet d'une feuille ; x 270. PLANCHE III. Fig. 12. Rhynchostegium isopterygioides. — a, plante, gr. nat. b, extremite d'un rameau; x 13. ••, d, e, f, ;/, feuilles; x 13. li, tissu basilaire d'une feuille; x 138. z°, tissu marginal vers le milieu d'une feuille ; x 138. j, sommet d'une feuille ; x 138. /r, feuille perichetiale intime ; x 13. Fig. 13. Dicranella pygmxa. — a, b, plantes; x 3. c, d, e, feuilles; x 26. /', tissu basilaire d'une feuille; x 138. g, sommet d'une feuille ; x 138. h, feuille perichetiale; x 26. i, j, capsules operculees, it, 1'etat sec; x 26. k, capsule mure, ouverte, a 1'etat humide ; x 26. I, fragment du peristome et de 1'anneau ; x 138. in, feuille de D. minuta (Hpe.) Broth.; x 26. Fig. 14. Hyophila Ascensionis. — a, b, plantes, gr. nat. c, extremite d'une tige; 13. , c, extremitd de deux tiges ; x 13. d, e, f, feuilles; x 32. g, tissu basilaire d'une feuille; x 138. h, tissu marginal d'une feuille, vers le milieu; x 270. /, sommet d'une IVuille ; x 138. Scot.Nat.Ant.Exp. y j TTT JULES CARDOT : LES MOUSSES DE ^'EXPEDITION NATIONALS ANTARCTIQUE ECOSSAISE.- PLANCHE I. ' -•-- ," + -n, • I, III I 11 ,/) w®mim \ Fig. 6. M'Farlane 4 Erakine, Lith.. Edta. Scot. Nat. Ant. Exp. Vol III JULES CAKDOT : LES MOUSSES DE L'EXPEDITION NATIONALE ANTARCTIQUE ECOSSAISE. PLANCHE II. Fig. 10. M'FarUine & Erakine, Lith-. E<1 in. Scot. Nat. Ant. Exp. yQi TTT JULES CARDOT: LES MOUSSES UK L'EXPEDITIOX NATIONALS A.NTARCTKM'E ECOSSAISE- PLANCHE III **A [( ! ' ' >' ' V . -' •• \ , :-\;' / '- : L, '>,' ', i ' U ii Fig. 12. Fig. 15. [9* |f| '^^^ / // SXi'^n1^ . ;»; i -^•xMIfe^ Fig. 14. M'Farlane & Erskine. Lith-, Edin. VI.-MARINE ALGLE OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. VL-MAEINE ALG^E OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION.1 P>y A. GEPP, M.A., British Museum, and Mrs E. 8. GEPP. (With Two Plates.) THE following is a combined list of the marine algse brought back by the Scottish National Antarctic Expedition, and communicated to us by Dr R. N. Rudmose Brown. They were gathered partly in the cold southern waters of the South Orkneys, and partly in tropical and subtropical waters off the coast of Brazil, at St Paul Rocks and St Vincent, Cape Verde Islands. The South Orkneys He about 45° W. long, and 61° S. lat. ; they are therefore situated outside the Antarctic circle, and far to the south- east of Cape Horn. No algae had previously been recorded from these islands, so far as we are aware, the nearest being from South Georgia, and described by P. F. Reinsch in Neumayer's Internationale Polarforschung, 1882-83: Die Deutschen Expeditionen, Bd. ii. (1890), pp. 366-449. CHLOROPHYCE.E. 1. MONOSTROMA ENDIVLEFOLIUM, A. and E. S. Gepp in Journ. of Bot., xliii., 1905, p. 105, tab. 470, figs. 1-5. Thallus sessilis, subnigrescenti-viridis, membranaceus, callo vix ullo, mox expansus, maxime et dense crispato-undulatus, haud laceratus, parvus, 2-4 cm. altus et latus, 60-67 n crassus ; cellulis geminis vel quaternis, in sectione thalli transversal! verticaliter rectangularibus, angulis rotundatis ; cellulis basalibus longissime caudatis. (Figs. 1-5.) Habitat. — Shore pools and exposed at low tide, February 4, 1903, Saddle Island, South Orkneys. The nearest allies of M. endivitefolium are M. Blyttii, Wittr., and M. splendens, Wittr. From M. Blytii it differs in having an excessively crisped, not lacerate, frond, and in being smaller. Also the cells of M. endiviiefolium seen in surface view are more widely separated than those of M. Blyttii. From M. splendens it differs in colour, 1 The majority nf the notes that follow, and of the figures that illustrate them, were published previously in the following papers: — "Antarctic Algai" (in Journ. of Bot., xliii., 1905, pp. 105-09, tab. 470); "Atlantic Algie of the Scotia " (torn, cit., pp. 109, 110) ; " Leptosarca : a correction " (torn, cit., p. 162) ; " More Antarctic Alga; " (torn, cit., pp. 193-196, tab. 472) ; "A New Species of Lessonia" (op. cit., xliv., 1906, pp. 425, 426) ; "Marine Algie" (in National Antarctic Expedition, in., British Museum (Natural History), 1907, 15 pp., 4 plates). VOL. III. 73 10 74 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. in not being coriaceous, in its smaller size, thicker thallus, and longer narrower cells as seen in section. Reinsch, in his list of South Georgian Algae (p. 420), quoted above, describes a new variety, inacrogyna of Ulva Lactuca. This plant is, lie says, composed of a single layer of cells, those at the base being very longly caudate. The former of these characters would place Reinsch's plant in Monostroma rather than in Ulva. The habit of var. macrogyna is, however, quite different from that of M. endivisefolium. It is broad, large and flat like Ulva Lactuca, and the size of the cells is much smaller than that of our plant. If we regard var. macrogyna as a Monostroma, these two plants are the only Antarctic species of the genus known to us. 2. ULVA LACTUCA, L. St Vincent, December 1, 1902. Geographical Distribution. — Cosmopolitan. 3. CH^ETOMORPHA, sp. A fragment. Between Rio and Bahia, off the coast of Brazil, December 20, 1902, lat. 18° 24' S., long. 37° 58' W. 4. MICRODICTYON CMBILICATUM, Zan. Off Brazil, same locality as No. 3. Geographical Distribution. — Mediterranean, Warm Atlantic, Warm Pacific, Indian Ocean, Red Sea. 5. BRYOPSIS PENNATA, Lam. St Paul Rocks, December 10, 1902. Surface. Geographical Distribution. — Warm Atlantic, Indian Ocean. 6. CAULERPA RACEMOSA, J. Ag., var. L-ETEVIRENS, forma CYLINDRACEA, Web. v. B. St Paul Rocks, December 10, 1902, lat. 0° 58' N., long. 29° 20' W. Shore. Geographical Distribution. — Warm Atlantic, Indian Ocean, Australia. Var. UVIFERA, Web. v. B. Off Brazil, same locality as No. 3. Geographical Distribution. — West Indies, Indian Ocean, Friendly Islands. 7. C. MURRAY:, Web. v. B. Off Brazil, same locality as No. 3. Geographical Distribution. — -Victoria Banks, Brazil. 8. CODIUM TOMENTOSUM, Stackh. Off Brazil, same locality as No. 3. Geographical Distribution. — -Mediterranean, North Atlantic, Cape of Good Hope, Indian Ocean, Red Sea, North Pacific, Australia. PH^EOPHYCE^E. 9. SARGASSUM VULGARE, Ag. Off Brazil, same locality as No. 3. St Vincent, shore, December 1, 1902. Geographical Distribution. — Warm Atlantic. The first record consists of fragments of plants with few and widely scattered leaves. The second specimen has many and crowded leaves, which are smaller than those of the Brazil specimens. The St Vincent plants agree exactly with specimens collected by MARINE ALG^E OP THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 75 the Challenger from the same locality, and preserved in the herbaria of the British Museum and the Royal Gardens, Kew. 10. GYMNOSORUS VARIEGATUS, J. Ay. Two specimens without fruit. Off Brazil, same locality as No. 3. Geographical Distribution. — Warm Atlantic, Warm Pacific, Red Sea. 11. STYPOPODIUM LOBATUM, Kiitz. Five 'specimens without fruit. Off Brazil, same locality as No. 3. Geographical Distribution. — Canaries, West Indies, Chatham Island. 12. DICTYOTA DICHOTOMA, Lam, Off Brazil, same locality as No. 3. These plants show a variation from the ordinary type, inasmuch as the two branches of the final dichotomy take on the narrow form characteristic of f. intricata. Below this final dichotomy the plants are quite typical, and the change is a sudden one. Mr Lloyd Williams has been so kind as to give us his opinion on one of the specimens, saying that this development is probably the result of unfavourable environment at a late stage of growth. He adds that he is able to bring about such a change artificially in laboratory cultures. It is recorded as having been taken at a depth of 36 fathoms — a very deep habitat for a Dictyota. But possibly it was caught floating free in the water ; and possibly it is a starvation- form. When an alga is fixed, it thrives in the food-bearing currents which sweep past it ; but if it should break off and float away in such a current, it would soon exhaust the food in its neighbourhood, and would then be in risk of starvation. And if carried down to an undue depth, it would pass out of the zone of optimum conditions of light, C02, etc. 13. PHYLLOGIGAS SIMULANS, comb. nov. Syn. Lessonia grandifolia, A. and E. S. Gepp pro parte in Journ. of Bot., xliii., 1905, p. 105, tab. 470, fig. 6. Lessonia simulans, A. and E. S. Gepp in Journ. oj Bot., xliv., 1905, p. 425 ; National Antarctic Expedition, iii., British Museum (Natural History), 1907, "Marine Algte," pp. 5-7, pi. ii., fig. 10. Phyllogigas grandifolia, Skottsberg pro parte in Wissen. Ergebn. Schwed. Siidpolar-Exp., Bd. iv., Lief. 6, 1907, pp. 63-69. Planta incompleta. Frons laminarioidea ut in P. grandifolia, stipite complanato ancipite suffulta, simplex, lanceolato-linearis, longa, lata (12'5 cm. plusve), marginibus iiitegerrimis. Laminae substantia pergamentacea vel coriacea, e stratis tribus composita ; cellulis corticalibus nionostromaticis quadratis granuloso-obscuris ; subcorticalibus oblongis parenchymaticis in circa 6-7 series dispositis ; medullaribus congestis elongatis augustis strictis 9-10-seriatis tubulos perpaucos subinfuudibuliformes vagina e cellulis parvulis composita vestitos foventibus. Ctetera desunt. (Figs. 6, 7.) Habitat. — Scotia Bay, South Orkneys, near surface, April 1904, R. N. Rudmose Brown. 76 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. The following details of the minute structure were published in the Report of the National Antarctic Expedition (loc. cit.) :— The lamina has a monostromatic cortex, or outer layer, composed of quadratic thin- walled cells with granular contents. Beneath this is a subcortical tissue consisting of about six layers of larger cells, rounded or oblong, lengthened parallel to the axis of the frond. And interior to this is the characteristic medulla, composed of some nine or ten rows of closely juxtaposed, narrow, elongated, and comparatively thick- walled cells, with a few ensheathed trumpet-hyphse scattered among them. The medullary cells are sometimes filled with a pale-brown mucilage, and their limits are then barely dis- tinguishable. Compare fig. 6 and its description. In the stipes the medulla is the main tissue, and consists of a dense, pale-brown mass of hyphse, chiefly longitudinal (fig. 7) and straight, but here and there mingled with interwoven hyphse. Scattered in the medulla are a very few trumpet-hyphse, some with and some without a sheath of very small cells. The outer cortex lies beneath a distinct superficial cuticle, and consists of three or four rows of small quadrate cells arranged in radiating lines, which, passing inwards, gradually change into a pluri-stromatic subcortex of large round and oblong cells, which in turn merges into the medulla. The structure of the holdfasts, or organs of attachment, rather resembles that of the stipes, but the strata are less definitely marked. There is a dense medullary mass of hyphse, without any trumpet-hyphse.. The outer cortex is composed of small, dense-coloured quadrate cells which, traced radially inwards, change gradually into larger and larger thin-walled subcortical cells, which in turn undergo transition into the medulla. As regards the systematic position of the plant, we had no doubt in our minds at first that it was conspecific with the type of our Lessonia grandifolia from Cape Adare. For the Scotia specimens, though fragmentary, suggested a striking external resemblance to the type. But later, when we had made a more careful comparison of the microscopic structure, we found ourselves compelled to separate the Scotia plant off as a proper species — Lessonia simulans. The most obvious difference between L. simulans and L. grandifolia is found in the medulla of the lamina. In L. simulans the medulla is a very pale-brown tissue of close-set elongated cells, with very few ensheathed trumpet-hypbse among them ; whereas in L. grandifolia the medulla is colourless and composed of hyphse mostly longitudinal, laxly juxtaposed, separated from one another by one or two times their diameter, and interspersed with numerous ensheathed trumpet-hyphse disposed in a wide median band. Another point of difference is found in the cortex, which in L. simulans is monostro- matic, and composed of quadrate cells with granular contents. In L. grandifolia the cortex is composed of short vertical crowded rows of small brown cells. But whether L. simulans differs essentially from L. grandifolia in habit or external characters, we are unable to say ; for the material of the former was incomplete. MARINE ALGJE OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 77 Dr C. Skottsberg (loc. cit.) criticised our separation of the two species; and in founding his new genus Phyl/oyigas he reunited them in its single species. His criti- cism provokes a wish to reinvestigate the Scotia material. Unfortunately, that material lias long since passed out of our hands — and indeed out of our memory. And at the time of writing this note we are far removed from access to slides, microscope, herbarium, books. But from what we can remember of the specimens, and from what we have written about them, we feel that Dr Skottsberg has failed to appreciate the structural differences which in our opinion separate the species. L. simulans may well be a species of PhyUogigas ; and we have now placed it therein as a second species, that is, distinct from P. grandtfolia. In treating of P. grandifoUa, Dr Skottsberg based his detailed description and his figures of the anatomy upon his own material gathered in South Georgia and Graham Land. But, as far as we can understand them, they appear to us to approach much more nearly to the structure of the type of P. simulans from the South Orkneys than to that of P. grandifoUa from Cape Ad are in Victoria Land — a conclusion which would be in agreement with the widely separated distribution of the two species in the Antarctic region. It should be added that Dr Skottsberg, when writing his paper, had not seen our fuller account and figures of these types published in the Report of the National Antarctic Expedition. For though our paper was already in type a month or two before we had the pleasure of making Dr Skottsberg's acquaintance, yet it was not actually published until a few weeks after his paper appeared. 14. ADENOCYSTIS LESSONII, Hook, and Harv. MacDougall Bay, South Orkneys, November 1903. Geographical Distribution. — Cape Horn, Falklands, Auckland and Campbell Islands, Cockburn Island, Wandcl Island, Kerguelen, Tasmania, and New Zealand. 1 5. DESMARESTIA Rossn, Hook, and Harv. Scotia Bay, South Orkneys, 1-3 fathoms, March 1, 1903. Geographical Distribution. — Cape Horn, Falklands. It is surprising that the Scotia collections contain no example of the plant called D. media in the Flora Antarctica, part ii. (1847), p. 466. It is a common species in the south polar region, and well represented in the Discovery collections ; but it is not — as Harvey supposed — identical with the northern D. media, Grev. (Sporochnus medius, C. Ag. ). We have been compelled to rename the southern species D. Harveyana. Our reasons for this have been given in the Report of the National Antarctic Ex/><'- /, iii. p. 7. FLORIDE^E. 1G. WILDEMANIA LACINIATA, De Toni ( — Porplnjra laciniata, Ag.). Buchan Bay, South Orkneys, March 25, 1903; Scotia Bay, South Orkneys. Geoij rap!i ical Distribution. — -Mediterranean, North Atlantic, South Georgia. 78 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 17. GELIDIUM CORNEUM, Lam. Two specimens without fruit. Also two fragments attached to Sargassum vulgare. St Vincent, December 1, 1902. Shore. Geographical Distribution. — Cosmopolitan. 18. CALLOPHYLLIS VARIEGATA, Kiltz. ? Scotia Bay, South Orkneys, July 1903. Geographical Distribution. — S.-E. Pacific, New Guinea, Kerguelen, Auckland Islands, and Straits of Magellan. This is a sterile and incomplete plant, and consequently we are unable to determine it with certainty. Its structure, as seen in a transverse section of an older part of the frond, much resembles that of Callophyllis vo,riegata. The thallus is composed of two strata, the interior consisting of large, thick-walled cells, separated from one another by smaller flexuose tubular cells, and passing into a cortex of small round cells, laxly and irregularly arranged in a cartilaginous matrix. The cortex is here and there invaded by a green endophyte, probably Chlorochytrium (fig. 8). In younger parts of the frond the cortex is monostromatic, and the interior has a fibrous appearance, owing to the collapse of the cells. As to the habit of the plant, the base is absent, and the fragment of thallus which we have seen is more or less palmately lobate and irregularly proliferous, membranaceous in texture, and coccineo-rosaceous in colour. The specimen is 7 cm. high and 9 cm. wide. C. variegata is of common occurrence about Cape Horn and the Falkland Islands, and our plant may be one of its broader forms. 19. ACANTHOCOCCUS SPINULIGER, Hook, and Harv. Scotia Bay, South Orkneys, 9-10 fathoms, May 1903 ; December 1903. Geographical Distribution. — Cape Horn, Falklands, Punta Arenas. 20. GRACILAKIA SIMPLEX, A. and E. S. Gepp in Journ. of Sot., xliii., 1905, p. 195, tab. 472, fig. 4 ; National Antarctic Expedition, iii., British Museum (Natural History), 1907, Marine Algae, pp. 9, 10. Syn. Leptosarca simplex, A. and E. S. Gepp in Journ. of Bot., xliii., 1905, pp. 108, 162, tab. 470, figs. 10, 11. Frondes plures (8-10) e callo minuto ortse simplices oblongse vel lato-cuneatae planse membranacese, 10-15 cm. longse (apice destructo), 3-8 cm. latse, c. 230 /« crassge, inferne in stipitem plus miuusve sensim angustatum, 1-3 cm. longurn attenuate, stratis duobus contextse, cellulis interioribus rotundato-augulatis magnis 2-3-seriatis pachydermis (frondis sterilis majoribus maxime leptodermis collabeutibus submonostromaticis) ; cellulis corticalibus filamenta rarnosa verticalia efficientibus, tetrasporangia magna cruci- atim divisa foventibus (frondis sterilis majoribus mouostromaticis). (Figs. 9-11.) Habitat. — South Orkneys, shores of Uruguay Cove, March 26, 1903 ; also Scotia Bay, June 1903. This species was also collected by the British, French, and Swedish Antarctic Expeditions. When first studying this species we had but a few sterile fronds before us ; and, noting the extreme thinness of frond, the large -celled monostromatic cortex, and the MARINE ALG.'E OF Tllti SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 79 thin-walled great interior cells (collapsing irrevocably when dry), we felt that we were dealing with a new genus allied to Gracilaria, and we gave it the name of Leptosarca. Subsequently we received from Dr Rudmose Brown a more complete plant, gathered in the South Orkneys, which with a few other algae had been overlooked in the Scotia, until that gallant ship was cleared out previous to being sold. This tine specimen bore ten fronds, some of them sterile and having the structure of Leptosarca, and others tetra- sporiferous — with large cruciate tetraspores, thicker-walled internal cells, and a cortex of short chains of cells arranged perpendicularly to the surface of the frond. Upon finding these characters in the sporangiferous fronds, we thought it advisable to transfer the species to Gracilaria, even though the conclusive evidence of the cystocarps is still lacking. The finest examples of this species that we have seen were shown to us by Dr Skottsberg, who collected them during the Swedish South Polar Expedition. In certain parts of the frond of G. simplex we noticed small filaments creeping round the cell-walls. Reinsch (loc. cit., p. 413, tab. xv. figs. 11-13) records two species of Entonema from South Georgia, endophytic in other algse ; but our plant does not agree with these, nor indeed with any other species of the genus. We have only the vegetative filaments of our endophyte, and we hesitate, therefore, to give any definite opinion on it. Since, however, the algse from South Orkneys are few and interesting, it is worth while recording it, as it may occur among other Antarctic collections. 21. EPYMENIA, sp. Scotia Bay, South Orkneys, 9-10 fathoms, May 1903. Two specimens without fruit. They resemble E. obtusa in general habit and structure, but they lack the midrib in the base of the flabellate branches. The length of the midrib seems, however, to be a variable character in E. obtusa. 22. PLOCAMIUM HOOKERI, Harv. Scotia Bay, South Orkneys, 9-10 fathoms, August 29, 1903; April 1903; May 1903. The last specimen is so covered with diatoms as to be unrecognisable until it is cleaned. Geographical Distribution. — Kerguelen, Heard Island, South Georgia. 23. P. COCCINEUM, Lynyb. Scotia Bay, South Orkneys, December 1903; 9-10 fathoms, May 1903. Geographical Distribution. — Cosmopolitan. 24. HYDROLAPATHUM STEPHANOCARPUM, A. and E. S. Gepp'm Journ. of Bot., xliii., 1905, p. 195, tab. 472, figs. 5-7. Frons fruticulosa 15-30 cm. alta irregulariter dichotoma 3-4 mm. lata valde costata alata, ala pinnativenia ssepe destructa, prolificationes uumerosas lanceolato-lineares costatas pinnativenias, venis oppositis couspicuis, monostromuticas usque ad 32 mm. longas et 4 mm. latas, e costis emittens. Cystocarpia adparenter pedicellata, revera in foliolis minutis transformatis e costa emergentibus sessilia, trichomatibus pluribus instructa. (Figs. 12-14.) 80 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Habitat. — Scotia Bay, South Orkneys, July 1903. This species is most nearly related to Delesseria sanguinea, Lam. , from which it differs in having the cystocarps not smooth, but more or less clothed with simple tapering appendages, chiefly disposed around the sides, and leaving the top bare. But for this wreath of appendages we should regard the plant as no more than an old narrow- leaved and very proliferous form of D. sanguinea. The question whether or not H. stephanocarpum belongs rightly to the genus Delesseria depends on the view held of the systematic position of D. sanguinea ( —Hijdrolapatliwn sanguineum, J. Ag.), with which species our plant must stand or fall. Agardh, attaching primary importance to the structure of the mature fruit, regarded Hydrolapathum as forming a distinct genus in Rhodymeniacese near Rltodo- phyllis, on account of its composite cystocarp with " nucleoli " separated by radiating columns of sterile threads, and on account of the carpostomium-structure. Schmitz, on the other hand, reunited Hydrolapathum with Delesseria on account of the similarity of procarpial development, which is a more primitive character than the mature fruit on which Agardh founded his conclusions. If we follow Schmitz and De Toni, our plant would be called Delesseria stephanocarpa. Our own inclination is, however, to follow a middle course. Instead of sinking Hydrolapathum into Delesseria, from which so many less well-marked genera have been quarried, we would maintain Hydrolapathum as an independent genus on the score of the structure of its cystocarps and sporophylls ; but we would place it in the Delesseriese, and not in Rhodymeniaceae. 25. PTERIDIUM PROLIFERUM, A. and E. S. Gcpp in Journ. ofBot., xliii., 1905, p. 107, tab. 470, figs. 7-9. Frons fruticulosa, circa 12 cm. alta, alterne dichotoma (sed ramificatio ob prolifi- catioues copiosas obscura) ; rarni complanati, costati, alati, costa inferne conspicua, superne attenuata, omniuo sine venis lateralibus ; rami ramulique laciuiati, a marginibus costaque prolificantes, alterne et irregulariter dichotomi. Ramuli ultimi membranacei, ligulati vel cuneato-ligulati, usque ad apices obsolete et simpliciter costati, irregulariter lacerati vel grosse dentati, prolificantes. Cellulse pagiualcs homceocystideae omnes rotundato-angulatse. Tetrasporangia sine online utroque latere costee phyllorum par- vorum disposita, soros nee in unum conflueiites, nee ad apicem attinentes formantia. (Figs. 15-17.) Habitat. — Scotia Bay, South Orkneys, 9-10 fathoms, May 1903. We should have preferred to style our plant simply Delesseria prolifera, using Delesseria in the old wide sense. But that genus, as emended by J. G. Agardh, is now so limited in its scope that we are compelled to refer the plant to Pteridium, although we regard it and certain other genera latterly split off Delesseria as too nearly allied to be worthy of generic rank. In our species the mode of branching is very much masked by the abundant proliferations. It is in habit most like P. alata and P. pleurosporum, but differs from the former in being much more irregularly branched, and in having no MARINE ALGM OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 81 lateral veins. From P. pleurosporum it differs in being very proliferous, and in the sori not being confluent over the costa. The sori, in fact, resemble those of Hypo- denticulatum as figured in Kiitzing's Tab. Phyc.,xvi. tab. 15, 1 ( = Pteridium ., J. Ag.). De Toui divides the genus Pteridium into three sections, the first of which contains species with a "frons teretiuscula," which our plant has not; the second section has an obsolete costa ; and the third shows a difference in the form and disposition of the cortical cells, which cover the costa and the frond, when seen in surface view, besides having lateral veins. Our plant therefore falls into none of these sections. It may be thought that P. proliferum approaches more nearly to Hypoylos- sitm ; but from that genus it differs in being branched, as well as proliferous. From Erythroglossum it differs in having proliferations emerging from the costa, and in the similarity in form and size of the cortical cells of costa and frond. It differs from Reinsch's Delesseria condensata in having a much less strongly marked costa, and in being proliferous. 26. PTERONIA PECTINATA, Schmitz ( = Polysiplwnia pectinata, Hook, and Harv.). Scotia Bay, South Orkneys, July and December 1903. Geographical Distribution. — Cape Horn, Falklands, South Georgia. Reinsch (loc. cit., p. 374), in his note on this plant, says he believes it had never been figured. But he had overlooked the coloured figure in Harvey's Nereis Australis, tab. xxvii., which represents part of the thallus of a specimen from the Falklands collected by Mrs Sulivan, spelt " Sullivan" on the original in Herb., Kew, where there is an original drawing showing the structure, habit, and cystocarp. One of the Scotia specimens was growing attached to Hydrolapathum stephanocarpum. 27. PTILOTA CONFLUENS, Reinsch. Scotia Bay, South Orkneys, October 1903. Three incomplete plants without fruit. Geographical Distribution. — South Georgia. This species is described and figured by Reinsch (loc. cit., p. 376, tab. iii. figs. 5-9). His figure of a portion of the frond, being reduced to one-third its natural size, is not very helpful in determination. The figures of the structure, combined with the clear diagnosis and remarks, are, however, enough to enable us to recognise our plant as P. confluens. Reiusch remarks that the axillary cell in his specimen has almost dis- appeared. In our plant it is still quite clear. 28. CRYPTONEMIA LUXURIANS, J. Ag. Off Brazil, same locality as No. 3. Geographical Distribution. — Brazil, Martinique. 29. FLORIDEA, A. and E. S. Gepp in Journ. of Bot., xliii., 1905, p. 193, tab. 472, figs. 1, 2. Frons cartilaginea plana, 23 cm. lata, irregularitcr lacerata et fenestrata laevis, stratis duobus contexta ; cellulis iuterioribus majusculis (35-70 n long., 15-25 /x lat.) irregularibus rotundato-angulatis vel plus minusve axin versus perpendiculariter elon- VOL. III. n 82 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. gatis sparsis cartilagine hyalina immersis hie illic filamento tenui inter se conjunctis ; cellulis subcorticalibus minoribus paucis rotundatis, corticalibus elongatis angustis (20-25 M x 4 M) congestis monostromaticis ; omnibus protoplasmate granuloso instructis. (Figs. 18, 19.) Habitat. — Scotia Bay, South Orkneys, March 25, 1903. This specimen consists of a broad, thickish, cartilaginous frond, recalling Iridtea, much rent and irregular in outline, about 23 cm. in length and width. No point of attach- ment is to be distinguished, and the thallus is ragged and slit at the margin and in the body of the frond — something like Kiitzing's figure of Iridsea cornea (Tab. Plnjc., xvii. tab. 20). Neither cystocarps nor tetraspores are present. The surface is smooth, and in some parts the cortex has been eroded, but in others it is quite uninjured. In transverse sections the interior of the thallus is seen to be composed of fairly large irregular cells, rotundato-angulate or elongated more or less perpendicularly to the surface, spaced out and embedded in a hyaline cartilaginous matrix. All the cells are lined with a granular protoplasm, and here and there show distinct thin strands of protoplasm from cell to cell. This broad interior tissue forms the greater part of the thallus, and is bordered on either side by a thin band of much smaller round cells, closer together and abutting on the cortex. The cortex is composed of a row of long, narrow, closely-packed vertical cells. There is no medullary stratum of filaments. In attempting to determine the systematic position of this plant, we have examined innumerable microscopic preparations of various genera without finding any structure resembling that of our plant. The total absence of a filamentous medulla prevents it from being placed in Kallymenia or Enliymcnia, which otherwise it somewhat resembles. We are very much puzzled by Reinsch's Kallymenia reniformis f. carnosa (Meeresak/enfl. v. Sii-d Georgien, p. 394), the medullary parenchyma of which he describes as a homo- geneous tissue of larger cells with wider lumen than in K. reniformis, and packed with starchy contents. He gives no figure, and his description is too incomplete to enable us to decide whether, or how far, his plant approaches ours. He states that his plant has a very different structure from typical K. reniformis, except for its cortex. Our plant differs from K. reniformis in having its cortical cells vertically elongate, and not rotundate ; and its interior cells often elongate perpendicularly, and not parallel to the surface of the frond. Though unable to indicate the genus to which this Scotia specimen belongs, we record our observations in the hope that fertile material gathered by one of the other Antarctic expeditions may give the clue to its identity. Since the above was written, it has occurred to us that this specimen might possibly be an aged incrassate plant of Gracilaria simplex. But as the material is no longer in our possession, we are unable to put this idea to the test. MARINE ALGJE OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 83 DESCRIPTION OF PLATES. (Figs. 1-6, 8-19 are reproduced from Journ. of But. ; and Fig. 7 from the Report of the National Antarctic Expedition — by kind permission of the Editor of the Journal of Botany and the Trustees of the British Museum respectively.) * Fig. 1. Monostroma endivixfolium. — Portion of plant, nat. size. Fig. 2. Caudate basal cells, seen in surface view, x 150. Fig. 3. Ditto, seen in longitudinal section, x 150. Fig. 4. Upper part of thallus, transverse section, x 150. Fig. 5. Ditto, surface view : it, showing cells in twos and fours shortly after division ; and b, when they are more evenly distributed, x 150. Fig. 6. Pliyllogigas simulants. — Longitudinal section of lamina, showing central strand of hyphfe, with one '' trumpet-hypha " in longitudinal, and one in transverse view, x about 150. The cells of the external layer are in reality quadrate, thin-walled, with granular contents, and not, as shown here, rotundate ami densely obscured. Fig. 7. Outer part of longitudinal section of stipes, representing the cortex composed of short perpendicular rows of small quadrate cells, which, passing inwards, change gradually into a pluriseriate subcortex of large round and oblong cells, which in turn merge into the medulla; this latter is composed of densely packed straight hyphoe ; only the external part of the medulla is shown, x 110. Fig. 8. Callophyllis varieijata '! — Transverse section of thallus, showing endophyte, x 288. Fig. 9. Gracilaria simple*. — Transverse section of fertile frond, showing tetrasporangia, x 288. Fig. 10. Outline of a sterile frond with eroded apex, nat. size. Fig. 11. Transverse section of thallus of same : ii, taken from margin, showing thick-walled cells; b, taken from middle of frond, where the cells have much thinner walls. In b may be seen filaments of Entonema creeping over the cell-walls, x 150. In fig. 11 the walls of the large interior cells are represented as two to four times as thick as they should be. The largest of the interior cells have a diameter of 200 /x.. The cortical cells measure 12-15 ^ long by 6-10 /j. thick. Fig. 12. Hydrolupatlnim stephanocarpum. — Portion of plant, nat. size. Fig. 13. Cystocarp, x 30. Fig. 14. Section of cystocarp sessile on sporophyll, x 30. Fig. 15. Pteridium pruUferu/ii. — Branch showing proliferations from margin and midrib, nat. size. Fig. 16. Tetrasporic branchlet with growing points, and showing, not cortex, but interior tissue, x 30. Fig. 16A. Apex of lobe, surface view, x 150. Fig. 17. Tetrasporangia, surface view, showing their subcortical position, x 350. Fig. 18. Floridea. — Transverse section of thallus, x 44. Fig. 19. Portion of same, showing cortex and interior cells, x 288. SCOT. NAT. ANT. Exi1. VOL. III. GEI>P : MARINE ALGJE — PLATE I. !/V ' '" 1. 6. j 8a ANTARCTIC ALG,E. m SCOT. NAT. ANT. Exr. VOL. III. GEPP : MARINE ALG^E — PLATE II. 10 • , ' -J _jtrr&*£'lf .* -V.. '«nw. 16 18. ANTARCTIC ALGJE. VII.-SOME SOUTH ORKNEY VII.— SOME SOUTH ORKNEY ALG^E.1 By E. M. HOLMES, F.L.S. THE following list2 comprises the calcareous algte submitted to me for identification by Mr R. N. Rudmose Brown, and, in addition, some fragmentary algfe found adhering to these. The specimens were all collected at the South Orkneys during the stay of the Scottish National Antarctic Expedition there from March to November 1903 :— PRASIOLA CRISPA, Ag.s tip. Alg., p. 146 ; Kiftz. Tab. Phyc., v. tab. 40, f. vi. ; De Toni, fti/U. Alg., i. p. 142. Saddle Island, Scotia Bay, Ferrier Peninsula, etc. Very common on rocks up to several hundred feet, wherever there is running water in spring. Distribution. — The species is cosmopolitan in distribution, including Graham Land and Cockburu Island, Antarctica. SCYTOTHAMNUS RUGULOSUS, De Toni, Syll. Alg., iii. p. 454. Scotia Bay, 9-10 fathoms, April 1903. Distribution. — Also recorded from the Magellan Straits and Falkland Islands. CRYPTONEMIA LUXURIANS, J. Ag. Sp. Alg., ii. p. 228. Scotia Bay, 9-10 fathoms, April 1903. The undulate margin and parchment-like consistence of this fragmentary specimen indicate that it belongs to the above species. It is recorded from south polar regions 1 >y J. G. Agardh from Montague's specimens collected in the Voyage au Pole Sud ; but Hariot failed to trace it in Montague's herbarium, and found only Delesseria Lyallii, Harv. It is therefore interesting to ascertain that the plant really does occur in the Antarctic Ocean. Distribution. — Canary Islands, Cape Verde Islands, Brazil, and Martinique. IRIDEA, sp. Scotia Bay. Minute cuneate fronds of about 1 cm. long occur on the stones received, in company with the Lithothamnia, but it is impossible to determine to which of the species known to occur in the Antarctic Ocean this plant belongs. PLOCAMIUM SECUNDATUM, Kiltz. Tab. Phyc., xvi. tab. 42. Scotia Bay, 9-10 fathoms, April 1903. 1 Reprinted from the Journ. of Bot., July 1905. 2 To this list of calcareous and other algoe, which Mr E. M. Holmes has kindly drawn up for me, I have added some notes on the distribution of the species. I have omitted a few species, also recorded in the lists of Mr and Mrs Gepp.— R. N. R. B. 3 This species was determined by Mr A. D. Cotton. — R. N. R. 11. 87 88 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. The specimens do not exceed 2 cm. in length, and occur on the stones bearing the Lithothamnia ; but there is no reason to doubt that they belong to this species. Distribution. — Also recorded from Cape Horn, Hermite Island, and Magellan Straits. PETROCELIS CRUENTA, J. Ag. Sp., ii. p. 490; Crouan, Fl. Finist.,p. 147, tab. 18, f. 122. Scotia Bay, 9-10 fathoms. This species occurs on the stones bearing the Lithothamnia. Although it is not in fructification, the absence of the zonate lines found in P. Middendorffii. Kjellm., and the thin basal portion of the thallus indicate P. cruenta, J. Ag. Distribution. — It does not appear to have been previously recorded from the Antarctic Ocean. Known from Europe and North America. LlTHOTHAMNION LICHENOIDES, Heydr. f. ANTARCTICA, Fosl. ? List of Sp. (1898), p. 7 ; Svenska Exped. till Magell., Bd. iii. No. 4 (1900), p. 70. L. autarcticum, Heydr. Lith. Mus. Paris (1901), p. 544. Scotia Bay, June 1903. Distribution. — Hermite Island, Falkland Islands, and Kerguelen. L. MAGELLANICUM, Foslie, f. CRENULATA, Fosl. in Kogl. Norske Vidensk. Selsk. (1904), New Calcareous Alga?, p. 3; op. cit., 1895, p. 8, fig. 8. Scotia Bay, 9-20 fathoms, July 1903. This plant is mixed with the two following on the same stones, but is the least abundant of the three. It differs from the type in having a zonate margin and irregular very shallow prominences on the surface, as in L. fecundum, but the surface is less shining than in that species. LITHOPHYLLUM DiscoiDEUM. Foslie, f. ^EQUABiLis, Fosl. in Kogl. Norske Vidensk. Selsk. (1904), p. 3 ; Svenska Exped. till Magell,, Bd. iii. No. 4 (1900), p. 73. Scotia Bay, 9-10 fathoms. This plant has a smooth discoid thallus, with the immersed receptacles visible, only when empty, as a number of circular depressions crowded on the central half of the thallus. The margin is minutely cracked or fissured, as in L. incrustans, Fosl. L. DECIPIENS, Fosl. in Svenslea Exped. till Magell., Bd. iii. No. 4 (1900), p. 71. Scotia Bay, 9-10 fathoms. These specimens are in bad condition, all the sporangia being empty ; they are crowded closely over the whole surface of the thallus, giving it a rough or minutely reticulated appearance. Distribution. — California and Fuegia. It is remarkable that L. rugosum, Fosl., which occurs with L. magellanicum and L. discoideum on the coast of Patagonia, does not occur on any of the stones from the South Orkneys. It is characterised by the prominent wart-like excrescences on the thallus, like those of L. colliculosum Fosl., from which it differs in the character of the sporangia. VIII. -CALCAREOUS AL(LE. VOL. III. 12 ^ VIII.-CALCABEOUS By M. FOSLIE, Trondhjem Museum. [EDITORIAL NOTE. — The following account of the two abundant species of calcareous algae occurring at the South Orkneys is extracted from a paper by M. Foslie dealing with the new calcareous algae of several of the Antarctic expeditions of recent years (Kcmyl. Norske Vidensk. Selsk., Trondhjem, 1904, p. 3). The death of Herr Foslie in November 1909 has prevented the revision and amplification of these notes by the author. They are consequently published in their original form. For a fuller account of these two species, and their geographical distribution, reference may be made to M. Foslie's paper on " Antarctic and Subantarctic Corallinacese " in Wissen. Ergeb. Schived. Siidpolar- Exp., Bd. iv., Lief. 5, Stockholm, 1907. — R. N. R. B.j LlTHOTHAMNION MAGELLANICUM, Fosl. f. CRENULATA, Fosl. mscr. Thallus ikke saa haardt faestet til underlaget som hos den typiske form, kanten mere ujevn og konceptaklerue tildels svagt nedtrykte i midten. Formen staar naermest f. Schmitzii (Har.) Fosl. mscr. (Lithoph. Schmitzii, Har.), og den minder ogsaa noget om f. taltalensis Fosl. mscr. fra Taltal i Chile. Den sidstnaevnte form udmerker sig ved lidt mindre celler og lettere affaldende konceptakeldaekke end hos den typiske form. — Ny Orkenoerue. Den skotske antarkt. eksp. Scotia. LlTHOPHYLLUM DISCOIDEUM, Fosl. mSCT. f. .EQUABILIS, FosL niSCT. Skorpen er tyndere og jevnere end hos hovedformen, og i et tversnit viser der sig tildels smaa kvadratiske mellemceller omtrent soin hos ArchsBolithothamnion. Arten staar meget naer L. consociatum fra Kerguelen. Jeg forbeholder mig derfor senere efter naermere undersogelse at fastslaa dens forhold til disse arter og muligens at opstille den som selvstaendig. — Ny Orkenperne. Den skotske antarkt. eksp. Scotia. 91 IX. -FRESHWATER ALG.E OF THE SOUTH ORKNEYS. IX.-FRESHWATER ALG^E OF THE SOUTH ORKNEYS.1 By F. E. FRITSOH, D.Sc., Ph.D., East London College (University of London). (With Two Plates.) A. INTRODUCTORY REMARKS IN the year 1905 1 received from Dr R. N. Rudmose Brown seventeen tubes of fresh- water and subaerial algsa collected by him in the South Orkneys, while acting as botanist to the Scottish National Antarctic Expedition (1902-04). I am glad to have this opportunity of thanking him for placing this interesting material at my disposal. Our knowledge of Antarctic freshwater algse is at present not very extensive. The first important contribution was that of Hooker and Harvey,2 based on the material collected by the Erebus and Terror in 1839-43. This was followed about thirty-five years later by two papers of Reinsch,3 containing a description of the algse collected by the Rev. A. E. Eaton on the island of Kerguelen. A later paper by Reinsch 4 deals with freshwater algse collected by Dr H. Will in South Georgia. Wille 5 has further described a few forms brought by C. E. Borchgrevink from the Antarctic continent, and De Wildeman a number of algse collected by E. Racovitza of the Belgian Antarctic Expedition.6 In 1909, lastly, there appeared the important contribution of Van Heurck on the diatoms of the same expedition.7 1 Revised and reprinted from Journ. Linn. Soc. Land., Hot., vol. xl., 1912, pp. 293-338. 2 J. D. Hooker, The Botany of the Antarctic Voyage of H.M. discovery ships "Erebus" and "Terror" in the years 1839-43 (Flora Antarctica), London, 1844 : " Alga- " (by W. H. Harvey and J. D. Hooker), vol. i. pp. 175-193 ; vol. ii. pp. 454-519. 3 P. F. Reinsch, " Species ac Genera nova Algarum aquse dulcis, quae sunt inventa in speciminibus in expeditiorie Vener. transit, hieme 1874-75 in Insula Kerguelensi a clar. Eaton collectis," Journ. Linn. Soc., Bot., xv., 1876 ; P. F. Reinsch, " Freshwater Algse collected by the Rev. A. E. Eaton (Alga? aqua; dulcis Insulw Kergnelensis) : Account of the Petrological, Botanical, and Zoological collections made in Kerguelen's Land and Rodriguez during the Transit of Venus Expeditions, 1874-75," Phil. Trans. Roy. Soc. Lund., vol. 1G8, 1879, pp. 65-92. See also W. Archer, " Note on the Freshwater Alg;t> collected by H. N. Moseley in Kerguelen's Land," Journ. Linn. Soc., Bot., xv., 1876, pp. 445-446 ; E. O'Meara, " On the Diatomaceous gatherings made at Kerguelen's Land by H. N. Moseley, H.M.S. Challenger," loc. cit., pp. 55-59. 4 P. F. Reinsch, "Die Susswasseralgenflora von Sud-Georgien," l>ie internalionale Polarforschung, 1882-83. Die deutschen Expeditions und ihre Ergebnisse, Bd. ii., Berlin, 1890, pp. 329-365, Jahrb. i.-iv. 5 N. Wille, " Mitteihnigen uln-r ciiiigi- von C. E. Borchgrevink auf dem antarktischen Festlande gesammelte Pflanzen : III. Antarktische Algen (by N. Wille) ; IV. ftariculii mutini, Kiitz., ans dem antavktischen Festlande (by .1. Holmboe)," Nyt Mmj,i~>nf. Naturvid,nd//,3?ra-cells ultimately proving to belong to the life-cycle of S. antarctica ;l it does not, however, seem probable. In the course of the previous paragraph reference was made to resting-cells of Scotiella, which appear to arise in the following way (PI. I., figs. 12-15). Kather rarely one finds individuals of this alga in which the contents are markedly contracted or more or less rounded off (figs. 12, 13, also 16) ; in such cases some or all of the wings appear irregularly folded and stratified, so that they no longer show up so markedly (cf. figs. 12 and 16). Various stages of this kind have been found which seem to form a complete series connecting the normal ScofiW/a-individual with large, thick-walled resting-cells (fig. 15), the general shape of which is rounded, while the membrane is double, with a more or less undulated outer layer. The formation of these resting-cells (akinetes) appears to be initiated by a swelling up of the wall of the individual, and the rounding off of its contents ; as a result of the swelling of the wall the outline of the wings is obscured, while the wall becomes more or less rounded off around the contracted contents (cf. figs. 13, 14); at the same time a stratification becomes apparent in the swollen wall, which subsequently becomes more strongly and markedly thickened (figs. 14, 15). The contents appear to undergo a gradual change during the formation of the resting-cells. At first (fig. 13), as in the ordinary individuals, we have a central mass of granular protoplasm with a cap of fat at either end ; as the contents round off, however, this fat disappears (used in forming the thick walH), and the mature resting-cell contains only granular protoplasm (fig. 15) — possibly with a certain amount of fat diffused through it. Resting-cells of the type just described are fairly common in parts of the yellow snow material, but I have not met with any structures which could be interpreted as germination-stages of these cells ; their further fate must therefore at present remain an open question. 1 If so, they might prove to be germination-stages of the resting-cells described in the next paragraph, but there is no evidence for this. 108 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. One other possible stage in the life-history of S. antarctica has been observed (PI. I., fig. 17). This consists of a delicate, more or less oval membrane surrounding four oblong individuals of irregular shape, in some of which a pyrenoid was discernible ; the irregular shape is due to the formation of various outgrowths on the surface of each individual. I have rather tentatively regarded these four cells as Scotiella-cella in the making, the outgrowths, which appear to be solid, being interpreted as the developing wings. Only two such stages have been observed, and they were both in the same condition, so that future observations must show whether the above inter- pretation is correct. Certainly no great stretch of the imagination is necessary to derive an ordinary ScotoWZa-individual from the oblong cells seen in fig. 17. If these stages really belong to the Scotiella, we still require to know whether they represent the division of an ordinary individual or of a resting-cell. We may next proceed to consider the systematic position of Scotiella. In view of our rather incomplete knowledge of the organism, its affinities are not easy to determine, but I am inclined to regard it as a fairly close ally of the genus Oocystis, from which it differs chiefly in its characteristic wings, and in the marked storage of fat. Should fig. 17 actually represent a reproductive stage of an ordinary individual of S. antarctica, then the latter organism would reproduce in a very similar way to Oocystis. The cells of the latter are described * as having one or more parietal chloro- plasts with or without pyrenoids ; so that the probable occurrence of a single chloroplast with a pyrenoid in the Scotiella does not speak against a relationship with Oocystis. The latter genus is included by Oltinanns2 in his Sceuedesmaceae, while Wille refers it to the Oocystacese.3 Before concluding the discussion of S. antarctica, reference must be made to the fact that the resting-cells (fig. 15) above referred to this species show considerable resemblance to Trochiscia insignis (Reinsch), Hansg. ( = Acanthococcus plicatus, Reinsch), and to T. obtusa (Reinsch), Hansg. ( = A. obtusus, Reiusch).4 In the former case the cells are much larger than the resting-stages ascribed to the Scotiella, but in the. latter case the dimensions approximately agree. It would, however, be inadvisable at the present moment to attempt any further comparison between these forms. (d) SCOTIELLA POLYPTERA, n. sp. (PL I., figs. 18-21). The second species of Scotiella, S. polyptera,6 n. sp., was, as above stated, only rarely found in the yellow snow material, but rather more abundantly in samples 1 1 and 15, from which all the figures were drawn (PL I., figs. 18-21). The material of this species was, however, so scanty, and the state of preservation of the 1 Cf. Wille, loc. cit., p. 58. 2 Oltmanns, Morph. u. Biol. d. Algen, vol. i., Jena, 1904, p. 183 d seq. 3 A full diagnosis of the new genus and species, with measurements, will be found on p. 125. 4 Of. Migula, Kryptoijamenfl. v. Deutschland, Deutsch.-Osterreicli u. d. Schweiz, ii. 1, p. 634, and pi. 35, E, fig. 5, pi. 35, F, fig. 10. 6 iroXus, many ; trepan, a wing. FRESHWATER ALGJE OF THE SOUTH ORKNEYS. 109 individuals so bad in most cases, that only a brief description can be given. The cells are oval, and of considerably smaller dimensions than those of S. antarctica ; in place of the six wings of the latter the cells are provided with numerous longitudinal wings, which generally have a somewhat spiral trend (fig. 18, and especially figs. 19 and 21). The wings do not stand off from the body of the cell nearly as prominently as in S. <(it/i'rf/fca, (c/. especially fig. 20, which is an oblique end-view of the organism). Each of the wings is undulated (fig. 18), and this fact, together with the large number of the wings, makes the cells present a notched crenate outline from whatever point they are viewed (cf. figs. '20, 21). At the two ends of the cells the wings bend inwards, and terminate in a shallow sinus (fig. 20, also 21 and 18). The wings are solid, as in the other species, and appear as flat crenations in optical section (fig. 20). As regards the contents of the cells of S. polyptera, in the few cases in which they could be made out at all there appeared to be a single chloroplast with a prominent pyrenoid (fig. 21); fat was not observed in the cell-contents of this species. Only one case of possible reproduction was found (fig. 19); a cell of S. polyptera, in which the outline of the wings had become obscure (visible, however, as delicate spiral lines in the right- hand portion of fig. 19), contained a number of elongated protoplasmic masses, in one of which a pyrenoid was prominent. This stage is possibly to be interpreted as division of the contents of the individual to form a number of daughter-individuals ; if this is so, it of course constitutes a marked analogy to the probable stage of S. antarctica shown in fig. 17. It may be added that the individuals of S. polyptera were not uncommonly found in groups of four or five, which would quite accord with their being formed by subdivision of a mother-individual. S. polyptera is obviously of a more dubious character than S. antarctica. While some doubt may justly be felt as to its independence (for it might be the zygospore of some form ? 1), it is impossible to feel quite certain of its close affinity to S. antarctica, and further observations may warrant its removal from the genus Scotiella. In view of the bad definition of the wings in all the cells observed, I am inclined to think that no normal individuals of S. polyptera were present in my material, and that all the forms observed were either preparing for division or passing over into some resting-stage.2 (c) PTEROMONAS NIVALIS, Chod. (PI. I., figs. 22-24, 31). Another form, of which, however, only very occasional specimens were met with in the yellow snow material, is represented in figs. 22-24 and 31 of PI. I. This is almost 1 I have not, however, met with anything to countenance this view. Lagertieim (" Schneeflora des Pichincha," Ber. Deutsch. Bot. Ges., x., 1892, p. 529 ; also "Schneeflora in Lulea Lappmark," Hot. Centralbl., xvi., No. 11, 1883) refers to oval cells (15^ broad and 30 /i long) as occurring in red snow from Amsterdamo (Spitsbergen). These cells are described as having longitudinal ridges, and may possibly represent the same form as S. polyptera, or a closely allied one. Lagerheim, however, regards these cells as probably being zygospores of Clilamydomonas lateritia (cf. p. Ill, footnote 1). 2 A diagnosis of Scotiella polyptera is given on p. 125. 110 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. certainly Choclat's Pteromonas nivalis.1 The individuals are of an elongated oval shape, and provided with a number of wings, which are rather sinuous and have a more or less marked spiral course (figs. 22-24). The number of wings has been determined as eight in individuals seen from the side, although none were seen in optical section, as Chodat figures them (his fig. 70, H and j). The behaviour of the wings at the two ends of the cells could not be exactly determined, but it would seem (fig. 23) as though they projected somewhat at these points so as to give rise occasionally to the appearance of a terminal papilla (cf. also Choclat's fig. 70, B, c, K) ; all the wings appear to run together to a common point. In the cell-contents an irregularly shaped, more or less central chloroplast with a pyrenoid was often visible, and a considerable amount of the characteristic fat was mostly present.2 No reproductive or resting stages were observed. It seems to me that the reference of this species to the genus Pteromonas is in no way certain.3 The genus includes a number of species, which are actively motile forms provided with two cilia. In the case of P. nivalis, however, no cilia have been recorded, nor was I able to make out any traces of them in the yellow snow specimens. On this point Chodat (loc. cit., p. 146) remarks, "cellules parfois mobiles, ordinairement immo- biles ; cils inconnus." Wille,4 in his later description of this species, does not refer to any movement ; in fact, he regards the winged cells as resting-stages (aplauospores), and looks upon certain cells (" spiudelformige, an dem einen Ende etwas abgestumpfte Zellen," p. 168), which he figures on pi. iii., fig. 46 (cf. Chodat's fig. 70, F), as zoospores of the Pteromonas, which had come to rest ; possibly my fig. 31 may correspond to these cells. In view of the fact, however, that neither Chodat nor Wille nor I have seen any trace of cilia on either type of cell, these interpretations appear somewhat forced. A much simpler view would be to regard the typical winged form (as shown in Chodat's fig. 70, A, B, c, and my figs. 22-24) as the normal motionless individual, and the unwinged cells (Chodat's fig. 70, F, Wille's fig. 46, and my fig. 31) as young individuals, possibly formed by division of the contents of a mother-individual, and in which wings have yet to arise (cf. Chodat's fig. 70, N) ; the correctness of this view depends mainly on the nature of the movement observed by Chodat. If my interpretation of P. nivalis is correct, it is obviously out of place in the genus Pteromonas, and must be referred to Scotiella as S. nivalis (Chod.), F. E. Fritsch. With the genus Scotiella it agrees in several respects, viz. the single chloroplast with a pyrenoid, the wings (cf. especially the optical section shown in Chodat's fig. 70, J, with my optical section of Scotiella antarctica, fig. 11), the behaviour of these wings at the two ends of the cell ("qui se 1 Cliodat, Algues vertes de la Suisse, Berne, 1902, pp. 145-146. 2 Chodat describes the cells of Pteromonas nivalis as " ordinaireraent remplie d'une huile jaune-doree " (p. 146), which may well correspond to the yellow fat observed in the individuals of the yellow snow. Wille (" Algologische Notizen, xi.-xiv.," Nyt Magazinf. Naturmdenshib, xli., 1903, p. 170), however, speaks of the contents of the cells being generally coloured almost quite red by h;ematochrome. This is interesting as indicating that one and the same snow form may exhibit different pigments in different localities. 3 Cf. Wille, loc. cit., p. 171. 4 Loc. cit. FRESHWATER ALGJE OF THE SOUTH ORKNEYS. Ill prolongent vers les cxtrdmites en arete saillante," according to Chodat, p. 140; "An beiden Enden des Zellinhalts finden sich Vorspriinge . . . sicherlich nur dadurch entstanden, dass die Rippen dor Membran etwas vorsprangen," according to Wille, pp. 1G9, 170; cf. also my fig. 23), and, lastly, the apparent formation of new individuals by subdivision of the cell-contents.1 (/) CHODATELLA BREVISPINA, n. sp. (PI. I., figs. 25, 26; PI. II., phots. 3, 5, Ch). A very typical and rather abundant member2 of the yellow snow flora is constituted by spiny ellipsoidal cells, which appear to belong to a new species of Chodatella, which may be styled C. brevispina (PL I., figs. 25, 26). The cells of this species are discoid and about 18 M long and 12 M broad, and are covered all over their surface with uniformly distributed spines. The latter are very short and, as a general rule, do not project beyond the surface for a distance greater than twice the thickness of the wall ; they are mostly rather delicate, but occasionally individuals bearing coarser spines were to be found. All the spines on a given cell are generally of about the same length, although some- times slight differences are noticeable. The cell-membrane is colourless, and consists of two well-marked portions, — a dark-looking outer (probably cuticular) layer and an inner much lighter layer. There appears to be a single chloroplast, although I do not feel certain of this ; a pyrenoid was not observed. Large quantities of fat are almost always present in these cells. In the majority of cases two more or less rounded masses are found, one at each end of the cell and separated by a central mass of granular protoplasm in which a considerable amount of starch frequently occurs (PI. I., fig. 26). Often one of these two fat-masses is considerably larger than the other, and occasionally only one large mass is present at one end of the cell. In some individuals, lastly, the fat predominates to such an extent that only a small amount of granular protoplasm can be distinguished, all the remaining part of the contents being obscured by the accumulation of fat (PI. I., fig. 25). The greatest difficulty in the way of a satisfactory determination of this form as a species of Chodatella lies in the absence of all reproductive stages. In CJiodateUa* reproduction is effected by subdivision of the cell-contents to form a number of new 1 Wille (Inc. n't., p. 171) also suggests on the basis of his observations that it may become necessary to remove /'. niralis from the genus Pteromonas ; this is based on his view that the ordinary winged cells are aplanospores (re.-, ting- cells), that reproduction is effected by small fusiform zoospores, and on the possibility of the cells containing several chloroplasts without pyrenoids (see loc. cit., p. 169). It does not appear that the last of these observations is correct ; the others have already been criticised above". Wille suggests that the oval cells provided with longitudinal ridges, referred to by Lagerlieim as having been found in red snow from Amsterdamo (Spitsbergen) (3, p. 124, and pi. iii., figs. 32-33. '•> Loc. cit., p. 124. FRESHWATER ALG^E OF THE SOUTH ORKNEYS. 113 same general shape and the cell-contents are often quite identical, there being two terminal globules of fat with intermediate granular protoplasm (fig. 27) ; a pyrenoid could not be made out. These cells, however, differ from those of C. brevispina in three prominent respects: they are always of smaller dimensions (length, 13-15 /x), they have a perfectly smooth, rather thin membrane devoid of spines, and the ends are commonly more or less pointed (fig. 27) and never rounded off to such a marked extent as is the case in C. brevispina (cf. even fig. 28 with figs. 25, 26). Were it not for the difference of shape and the absence of all intermediate stages, these cells might be regarded as young individuals of the latter ; but as it is, this view is scarcely permissible. Similar though somewhat larger cells appear to have been observed by Lagerheim l in red snow from Mount Pichincha in Ecuador ; he suggests that they may belong to some member of the Volvocinese. It seems much more likely, however, that they represent a species of Oocystis. In one or two cases a considerable number (about sixteen) of these cells was observed lying within a common mucilaginous investment, which would point to some species like Oocystis lacustris, Chocl., or 0. glceocystiformis, Borge. There are further resemblances to 0. lacustris in the pointed shape of the cell, in the (probably ?) single chloroplast, and in the occurrence of oil-drops in the latter species ; 2 also in the very feeble thickening of the ends of the cells in O. lacustris? a feature which is much more pronounced in other species of the genus. For these reasons I am inclined to regard the cells shown in figs. 27 and 28 as merely a form (f. nivalis) of O. lacustris, Chod., characterised by the prominent storage of fat;4 the cells, which Lagerheim observed, may possibly belong to the same species. (h) SPH^ROCYSTIS SCHROETEEI, Chod., f. nivalis, n. f. (PI. II., phot. 2, S). In sample No. 3 of the yellow snow an organism (text fig. 1, F and G, p. 122) was very abundant, which seems to be referable to the genus Sphivrocystis of Chodat.5 This form consists of larger or smaller groups of round or oval cells (text fig. 1, F). green in colour and with granular contents, embedded in very soft mucilage, the outline of which is often irregular, but sometimes roughly circular (particularly in the case of the smaller colonies). The cells are separated by considerable intervals from one another, and mostly show a very uniform distribution (text fig. 1, F) ; the intervening mucilage is quite structureless and invisible. Each cell has a delicate bounding membrane of its 1 Lagerheim, "Schneeflora ties Pichincha," Ber. Deutsch. Hot. Ges., x., 1892, p. 525, footnote 2 : "Zahlreiche ovale Zellen, 6-10 n dick und 10-20 ^ lang, welche grunen Inhalt und an den Enden je einen zuweilen rothlichen (Eltropfen fiihrten. Sie lagen immer isoliert und konnten nicht zur Entwickelung gebracht werden." 2 Cf. Chodat, "Etudes de Biologie lacustre," Bull. Herbier Boissier, v., 1897, p. 296 ; also Algues vertes de la Suisse, Berne, 1902, p. 190, fig. 105. 3 Chodat's figures in most cases give very little indication of this thickening, which was not to be found iu the Antarctic specimens. The latter may possibly have been relatively young individuals, a view which is supported by the thinness of the walls. 4 See also p. 124. 5 Chodat, " Etudes de Biologie lacustre," Bull. Herbier Boissier, v., 1897, pp. 292-295, pi. ix. ; also Algues vertes de la Suisse, Berne, 1902, pp. 114, 115, fig. 53. According to G. S. West (Journ. Linn. Soc., Bot., xxxix., 1909, pp. 75, 76) Sphserocystis schroeteri, Chod., and Tetraspora lacustris, Lemm., are synonymous (cf. also Chodat, Alg. vertes, p. 115). VOL. III. 15 114 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. own ; the shape of the cells is mostly spherical, but sometimes slightly oval, and a kind of colourless beak is often to be seen on one side. In a few cases, especially after staining with iodine or gentian violet, it appeared as though there were a pair of short cilia arising from this beak and attached close together. All attempts to obtain clearer preparations were, however, unsuccessful, and the presence of cilia in the Antarctic form must therefore remain doubtful. I have been able to make out only very little of the cell-contents ; a small round body (probably a pyrenoid) can generally be detected, and there was commonly a small colourless area beneath the beak at the front end of the cell, but the chloroplast could not be properly deciphered. The cell-contents frequently contain starch, but fat was generally completely absent in these colonies. Apart from the normal colonies just described, two other kinds of colonies were observed. Firstly, such as showed many or all of the cells in process of bipartition ; and, secondly, colonies in which most or all of the cells had their contents divided up into a considerable number of smaller cells (generally about eight). The latter have a very characteristic appearance (fig. 1, G), and are on the whole commoner than the other two types. The small cells in these colonies are often distinctly ovoid and pointed at one end. They are generally more or less filled with the all-pervading fat, which appears to arise in the cells of the normal colony at the time of their division ; for whereas the cells of the normal colony are, as above mentioned, quite devoid of fat, occasional colonies are to be found in which the cells contain considerable quantities of fat, and in these one or other of the cells are always in process of division. The genus Sphserocystis was described by Chodat1 in 1897; subsequently Wille2 endeavoured to identify S. schroeteri, Chod., with Glceococcus mucosus, A. Br.,3 a view that was opposed by Chodat in a later paper,4 mainly on the grounds of the marked difference in size of the colonies in the two genera and the absence of cilia in his form. There seems, however, to be some evidence for the synonymy of the two genera, although the species are not necessarily identical ; for the present they are probably best kept distinct. Chodat failed to observe the cilia on the cells embedded in mucilage, stating definitely "pas de pseudo-cils " ; Wille does not say whether he observed them, although, as he makes no negative statement, it is to be presumed that he did.6 Wille6 describes as especially characteristic a clear space having the shape 1 Chodat, foe. cit. 2 Wille, " Algologische Notizen, xii., Uber Glceococcus mucosus, A. Br.," Nyt Magazin f. Naturvidenskab, xli., 1903, pp. 163-166. 3 Cf. A. Braun, Betrachtungen uber die Erscheimmg der Verjiinguiig in der Natur, Leipzig, 1851, p. 169 (Bug. trans, by A. Henfrey, 1853, p. 159); also A. Braun, "Uber Chytridium, etc.," Abhandl. Kgl. Ak. d. Wiss., Berlin, 1855, pi. v., figs. 5-20. 4 " Quelques points de nomenclature algologique : I. tiphserocystis, Cliod. ou Glcnococcus, A. Braun ? " Bull. Herbier Boissier, 2nd ser., iv., 1904, p. 233. s There is also no mention of the cilia in Wille's description of Glceococcus in Engler-Prantl, Die Natiirl, Pflan- zenfam., Nachtr. z. 1 Teil, 2 Abteil., Leipzig, 1909, p. 18. 6 Wille, " Algologische Notizen, xii.," foe. cit., p. 1 65. This space is here, probably as a result of a misprint, described as occurring in the back part of the cell ("im hinteren Teile der Zelle"). Cf. however fig. 5, A (p. 19), in Engler- I'rantl, he. cit. FRESHWATER ALG.-E OF THE SOUTH ORKNEYS. 115 of an inverted funnel ("verkehrt trichterformiger Raum") at the front end of the cell. This, I believe, coincides with the colourless area beneath the beak in the cells of the yellow snow form, although my material was not sufficiently well preserved to enable me to make out its exact shape. Apart from this, however, the Antarctic form agrees also in other respects with the descriptions of A. Braun, Chodat, and Wille. Chodat's fig. 53, B (Algu.es vertes de la Suisse) very much resembles the normal colonies above described, although all the cells were generally not as spherical as his figure shows them.1 His fig. 53, D (cf. also Wille, in Engler-Prantl, loc. cit., fig. 5, D) shows a similar subdivision of the cell-contents into a number of small parts, as in text fig. 1, G (p. 122) ; in my material, however, the membrane of the mother-cell always remained intact till division was complete,2 and the Schizochla/mys-like stages figured and described by Chodat were not observed. The most noticeable points of difference between the yellow snow form and Braun's and Wille's Glceococcus lie in the small size of the colonies and possibly in the shortness of the cilia, which are stated to be very long in the latter form, although those which I believe to have observed were invariably rather short. There can be no doubt that the three types of colonies found in the yellow snow material and above described belong to one and the same form, as numerous connecting- links were observed. Rather rarely isolated cells of the Chlamydomonas-type were met with in the material ; some of these certainly belong to species of Chlamydomonas (cf. p. 118), but others may well be single swarmers of the Sphterocystis-colomes. Occasionally one finds more or less rounded granular cells with a wide envelope of delicate mucilage around the very delicate cell- wall ; these cells agree in all respects with those of a normal colony, and it seems very probable that such stages constitute the commencement of a new colony. I have, however, been unable to demonstrate cilia in these cells. The chief differences between Sphserocystis schroeteri, Chod., and Glceococcus mucosus, A. Br., on the one hand, and the yellow snow form on the other, may be summarised as follows: — (1) The colonies of the latter are frecpaently rather more irregular in shape than those of the former ; (2) the cilia, if present, are much shorter; (3) the cells are of somewhat smaller dimensions and more frequently oval in shape ; (4) Sehizochlamys-]\ke stages have not been observed ; (5) the storage of fat. As I cannot feel certain of the occurrence of cilia in the yellow snow form, it will be best referred for the present to 8ph&rocystis schroeteri, Chod., as a forma nivalis* It is of considerable interest that so abundant a plankton-form as Sphserocystis should form an important constituent of the yellow snow flora. 1 An oval cell is, however, shown in the lower part of the colony. - In one or two cases the membrane of the mother-cell was pronouncedly thickened, appearing gelatinous and stratified. 3 Cf. p. 123. 116 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. (i) TROCHISCIA ANTARCTICA, n. sp. (PI. I., fig. 30). I have already referred to the abundant occurrence of species of Trochiscia in the material from the South Orkneys ; one of them is characteristic for the yellow snow flora (PL I., fig. 30), although not particularly common. It consists of isolated spherical cells with a thick and rather gelatinous-looking wall, which is uniformly covered with small processes. The latter have typically the shape of truncated wedges with the truncated surface outermost, so that the cell presents the appearance of a cogged wheel. There is, however, considerable variety in the degree of differentiation of these processes, all transitions having been found from cells in which the processes are but feebly indi- cated (probably young daughter-cells?) to such as have very prominent processes; in the latter case they are often of slightly unequal length. The processes appear to be interconnected by a network of ridges. The cell-contents were always a little con- tracted ; they appeared granular and often showed a well-marked central pyrenoid. Starch is always present, but fat is rare in this form, although now and again cells were found with quite a large quantity of it. This species of Trochiscia appears to show some resemblance to T. halophila, Hansg., and T. reticularis (Reinsch), Hansg.,1 but both these species have larger cells, and there are differences in the character of the membrane. The yellow snow form may pro- visionally be regarded as a distinct species, T, antarctica, n. sp., characterised by the peculiarly shaped processes on the membrane, the thick walls, and the faculty of fat- storage.2 Attention may, however, be drawn to the similarity between this form and the zygospores of two species of Chlamydomonas, viz. C. nivalis (Sornmerf. ), Wille,3 and C. globulosa, Perty ; * especially in the latter case there is some considerable resemblance. The character of the contents of Trochiscia antarctica was, however, not at all like that of a zygospore, since as a general rule no great quantity of food-reserves was present ; and nothing to indicate any relation to a species of Chlamydomonas was observed in the material. In fact, T. antarctica presents more the appearance of an independent alga than many other species of the genus do. (j) RAPHIDONEMA NIVALE, Lagerh. (PI. I., figs. 32, 33). A not uncommon member of the yellow snow flora consists of short filaments of three or four (but occasionally many) cells running to a point at one or both ends (PI. I., figs. 32, 33). The cells are provided with a very thin membrane, and contain but a single chloroplast without a pyreuoid. The filaments were generally more or less curved (fig. 33), and when only one end was pointed the other was rounded oft" (fig. 32). These filaments are undoubtedly referable to Lagerheim's genus Raphidonema.5 He observed 1 Hansgirg, Prodromus d. Algenflora v. Bohmcn, ii., Prague, 1892, pp. 240, 241. 5 A full diagnosis of Trochiscia antarctica will be found on p. 123. 3 Wille, " Algologische Notizen, ix.-xiv.," Nyt Magazinf. Naturvidenskab, xli., 1903, pi. iii., fig. 45. 4 Cf. Chodat, Algues vertes de la Suisse, Berne, 1902, p. 132, fig. 60, D. 6 Lagerheim, " Schneeflora des Pichincha," Ber. Deutsch. Bot. Oes., x., 1892, p. 523, and pi. xxviii., figs. 15-21. FRESHWATER ALGM OF THE SOUTH ORKNEYS. I 1 7 vegetative reproduction of this form, the threads breaking into two halves, each of which has at first one pointed and one rounded end. The stage shown in my fig. 32 undoubtedly shows one of the products of such a division. Subsequently, according to Lagerheim, the round eud grows out into a new hair-like point. Most of the individuals found in the yellow snow were of narrower dimensions than Lagerheim's form, and the cells were rather longer (fig. 33) ; but filaments were found here and there quite agree- ing with Raphidonema nivale, Lagerh., and there is no reason to regard the forms in the yellow snow as distinct from this species. In his recent revision of the green algae Wille1 includes Lagerheim's Raphidonema, in the genus Raphidium, Iviitz. (—Anldstrodesmus, Corda) ; this is in agreement with Chodat's earlier view.2 It seems a little questionable, however, whether this is really warranted. The typical species of the genus Raphidium are unicellular or colonial forms, in which reproduction is effected by transverse division of the contents (frequently into four), followed by elongation of the segments, so that they ultimately come to lie side by side as a number of daughter-individuals within the mother-cell (so-called auto- spore-development). This has not been observed in Raphidonema nivale. On the other hand, although septate Raphidiums have been described (e.g. R. pyreiiogerum, Chod., and R. nivale, Choc!.3), the breaking up of the septate individual into two parts by fragmentation is not known for this genus. The resemblance of Raphidonema to Raphidium therefore appears to be purely superficial, and one must agree with Lagerheim's original view,4 which regarded this snow alga as a member of the Ulotrichales, probably to be included in the Chfetophoracese ; the peculiar method of vegetative reproduction may, however, indicate a relationship to Sttehococcus,b and until more is known about Raphidonema its exact position must remain doubtful. Very rarely forms were found of the type shown in PI. I., fig. 34. This shows a single cell of the Raphidium-typc (diam. 2 M) with a prominent central pyreuoid. This is probably a species of Raphidium, possibly R. pyrenogerum, Chod., which is distinguished by having a pyrenoid, but Chodat's species appears to be much broader. I have seen too few individuals to be sure of the specific determination. Filamentous forms are poorly represented in the yellow snow flora. The most abundant is Ulothrix subtilis, Kiitz., of which relatively short filaments were always to be found embedded among the numerous unicellular and colonial constituents (PI. II., phots. 1, 2, £/"). Next in abundance comes R. nivale, Lagerh., which has already been considered. Lastly, very occasional filaments of a broad species of (Edogonium (diam. cell = 20 /u) with well-marked caps were observed. 1 Wille, in Engler-Prautl, Die Xntiirl. I'ftunsenfam., Xachtr. z. 1 Teil, 2 Abteil., 1909, p. 68. 2 Chodat, "Flore des neiges du col des Ecandies," Bull. Herbier Boissier, iv., 1896, p. 886. It does not aeem that Chodat's Raphidiim nivale is in any way allied to Raphidonema. 3 Chodat, Algues vertes de la Suisse, Berne, 1902, p. 200, fig. 120. 4 Loc. cit., p. 523. 5 Cf. Lagerheim, loc. cit., pp. 523, 524. 118 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. The remaining algse found in the yellow snow are very rare. These include forms like Pleurococcus vulgaris, Menegh., Mesotssnium endlicherianum, Naeg., Chlamy- domonas caudata, Wille, Nostoc minutissimum, Kutz., and probably other species of Chlamydomonas. Lastly, mention must be made of large round cells with a smooth and fairly thick membrane, and filled with yellowish-red or reddish, homogeneous or somewhat granular contents (text fig. 1, D, p. 12:2) ; the contents were commonly slightly contracted away from the wall on one side of the cell. These cells are of large size (diam. = about 40-60 P} — often as big as or bigger than the largest Chlorosphiera-cells— and although rare are very easily recognised when present, owing to their distinctive colour. These cells rather recall some figured by Wittrock,1 and referred by him to Chlamydomonas (Sphserella) nivalis (Sommerf.), Wille, but owing to their large size (about 52 M) it may be doubted whether they really belong to this species. Except for their larger size, there is also some resemblance to the resting - cells of C. sangitinea, Lagerh.2 In sample No. 2 a fungus was frequently to be found which, judging by its goni- diophore, was a species of Penicillium. A second fungus occurred in the other two samples, but could not be determined.3 In concluding this consideration of the yellow snow flora, attention may be drawn to one or two general features. The flora is practically entirely composed of green algas (except for the above-mentioned species of Nostoc}. Diatoms are represented only by fragments of frustules, and there are very few even of these. The plankton character of the whole flora is also a point of interest, and indicates that it may have arisen in part by spores of plankton-forms being carried by the wind on to the surface of the snow. This probably applies to all snow floras. C. EED SNOW.4 The three samples (Nos. 4-6) of red snow included in the collections from the South Orkneys were all of them very poor in algal forms, showing that red snow in 1 V. B. Wittrock, " Om snbns och isens Flora, etc.," in A. E. Nordenskiold, Stiidier och forskningar, etc., Stockholm, 1883, pi. iii., fig. 2. 2 Lagerlieim, loc. cit., pi. xxviii., fig. 1. It having been suggested to me that the cells above described might be cysts of rotifers, I sent some material of yellow snow to Mr James Murray, who very kindly informs me that the cells in question are quite unknown to him and not rotifers. On the same authority I am able to state that the yellow snow includes yellow cysts (100-1 50 /t) of bdelloid rotifers and a species of Colkmbola. 3 Tufts of short threads, richly branched in an arborescent manner and composed of spindle-shaped cells, 1 M or less in diameter. Cells thickest at a point about two-thirds of their length from the base ; from this point they taper gradually towards the base and rapidly towards the apex of each cell. 4 So many accounts of red snow have already been published, that a general consideration seemed unnecessary, and the following account deals solely with the components of the samples of red snow from the South Orkneys. The most important contributions on the subject of red snow are : V. B. Wittrock, " Om snbns och isens Flora, etc.," in Nordenskiold, Studier och forskningar, Stockholm, 1883, pp. 65-123, and pi. iii. ; Lagerlieim, "Bidrag till kannedomen om snofloran i Lulea Lappmark," Bot. Notiser, 1883 ; Lagerheim, "Die Schneeflora des Pichincha," Per. Deutsch. Bot. Ges., x., 1892, pp. 517-534, pi. xxviii. ; Lagerlieim, "Bin Beitrag zur Schneeflora Spitzbergens," Nuova Notarisia, 1894 ; Chodat, "Flore des neiges du col des Ecandies," Bull. Herbier Boissier, iv., 1896, p. 881 et seq. and pi. ix. ; Chodat, Algues vertes de la Suisse, Berne, 1902, pp. 95, 96. FRESHWATER ALGJE OF THE SOUTH ORKNEYS. 119 this region does not attain to nearly so abundant a development as yellow snow.1 The number of species present is also smaller. On the whole sample 4 was richer in individuals than either 5 or G, and showed a somewhat different constitution. Nearly all the forms present were in the resting condition, so that some doubt attaches to certain determinations. The samples of red snow included a good deal of non-algal matter, such as hairs, starch grains, pollen grains of Podoearpiis, etc. In comparison with the flora of the yellow snow we have to note certain similarities and certain differences. Among the former we may reckon the occurrence of character- istic forms of the yellow snow flora, such as Scotiella antarctica, F. K. Fritsch, and Raphidonema nivale, Lagerli. The former was found only in samples 5 and 6, especially in the latter; the number of individuals was small, but those present were of exceptionally large size (length of cell about 55 M). They appeared to contain the same yellowish fat as in the yellow snow forms ; no resting-stages were observed. The Raphidonema was quite common (especially in sample 4), and in this case agreed absolutely with Lagerheim's description. Apart from fragments of an (Edogonium it was the only filamentous form present. There are two marked differences from the yellow snow flora. These are («) the immense preponderance of red spherical cells, no doubt constituting the resting-cells of different members of Chlamydomoiiadacese (see below), and (l>) the occurrence of various diatoms in all three samples. The resting-cells are of two chief types, viz. with and without a broad mucilage-sheath. The latter type are circular, with a smooth, somewhat thickened membrane and granular contents, with a central pyrenoid (text fig. 1, A, p. 122); the diameter of these cells varies between 10 and 20 M. The red colouring matter in the contents had been for the greater part taken up into the preserving fluid, and the cell-contents appeared colourless or slightly greenish ; it is therefore impossible to say what the exact colour of these cells was in nature. A considerable quantity of fat was often present in these resting-cells. They recall very markedly the resting-cells (aplanospores) of Chlamydomonas nivalis (Sommerf.), Wille ( = Sphserella nivalis, Sommerf.), as figured by Wittrock.2 As very few other stages of this alga were found, the determination must, however, remain somewhat doubtful. In one or two cases subdivision of the contents into a number of parts was observed, but this, of course, scarcely aids in determining the species. The second type of resting-cell (observed only in sample 4) closely resembles the other type except that the cells are surrounded by a broad sheath of mucilage often about two to three times the width of the cell in diameter (cf. text fig. 1, C, p. 122 3) ; in many cases the mucilage was of a deep red colour, probably owing to the colouring matter of the cell having diffused out and stained the mucilage under the influence of the preserv- 1 Cf. also the remarks on the distribution of red and yellow snow cited on p. 99, from Dr R. N. Rudmose Brown's letters. 2 Wittrock, luc. cit., tub. in., fig. 1. 3 The mucilage-sheath was often considerably broader than is shown in this figure. 120 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. ing fluid. This deeply-coloured mucilage made details of the enclosed cell difficult to determinej but so much could be seen that it has a moderately thickened wall and granular contents ; a pyrenoid (?) was only very rarely visible. Numerous small particles were generally adhering to the surface of the mucilage, and this still further obscured the enclosed cell. The resting-cells of the second type were far less numerous than those of the first. They appear to correspond to cells observed by Lagerheim,1 and referred by him to Chlamydomonas, sp. ; similar cells were noticed by Wittrock.2 I am unable to add to our knowledge of these cells, and have consequently merely described them in the systematic portion of this paper as Chlamydomonas, sp. (?). In- asmuch as these cells are of about the same dimensions as the smaller resting-cells of the first type (described above), and as the two kinds of cells occur side by side, they may be merely different stages of the same organism. Apart from the forms hitherto mentioned, the only other constituents of the red snow from the South Orkneys are diatoms, which are, however, found only as isolated individuals (Melosira sol, Kiitz., Coscinodiscus radiatus, Ehrb., etc.). It seems probable that only the red restiug-cells above described and the Raphidonema are true components of this flora, and that the remaining forms are introduced by the agency of wind and (?) animals (possibly the penguins). The Scotiella is perhaps an introduction from the yellow snow flora (which is sometimes not very far separated from the red snow, cf. p. 99), while the diatoms (which are in great part marine forms) probably come from the seashore. The complete list of algse found in the red snow from the South Orkneys is as follows :— Chlamydomonas nivalis (Sommerf.), Wille (?). Melosira sol, Kiitz. „ sp. (cf. above). Coscinodiscus radiatus, Ehrb. Scotiella antarctica, F. E. Fritscb. Navicula borealis (Erhb.), Kiitz. Raphidonema nivale, Lagerh. Amphora ovalis, Kiitz. (Edogonium, sp. Triceratium, sp. (T. ardicum, Bright?). Zi/gnema, sp. (one filament). D. SYSTEMATIC ENUMERATION OF FRESHWATER ALG^E FROM THE SOUTH ORKNEYS. A. ISOKONT^]. CHLA MYDOMONADA CE^E. 1. CHLAMYDOMONAS CAUDATA, Wille, Algol. Not., xi., Nyt Magazin f. Natur- videnskab, xli., 1903, pp. 115-118 and 135-136, pi. iii., figs. 4-11 (PI. 1., figs. 35-40). Samples 10 and 11, abundant ; also as a rare form in the yellow snow. This and the following species are the only forms found in the material from the South 1 Lagerheim, Ber. Deutsch. Bat. Ges., x., 1892, pp. 523, 529, pi. xxviii., fig. 10, 2 Wittrock, " Om snbns och isens Flora," loc. cit. FRESHWATER ALGvE OF THE SOUTH ORKNEYS. 121 Orkneys that were obviously preserved in an active, motile condition. The prominent features of this species, as described by Wille, are the protrusion of the posterior end of the individual into a conical tip (figs. 37, 38), which is often somewhat bent to one side (fig. 36), the fact that the two cilia are about equal in length to the body of the cell, and that the strongly thickened base of the chloroplast contains a median rounded pyreuoid (figs. 37, 38). There can be no doubt that the individuals observed belong to this species, although one or two minor points of difference were noted. The cilia were frequently found to be as much as one and a third times the length of the cell (not shown in the figures) ; they were nearly always curved back or spread out at right angles to the body of the cell (figs. 37, 38), as Wille shows them. The size of the ordinary individuals varies considerably ; length = 13-20 M, breadth = 7-10 M, but some of the dividing individuals are much larger. The pointed posterior end, as a general rule, lies in the same straight line as the axis of the individual, but bending was not uncommon. The cell-membrane is almost invariably much more prominently thickened at the pointed posterior end, and not uncommonly individuals are found in which the whole of the pointed portion consists of solid membrane (fig. 39). In many cases (cf. Wille, loc. cit.) the posterior part of the protoplasmic contents is also pointed and in the living individual probably in direct contact with the pointed cell-wall, although in preserved material generally separated from it by a space (cf. how- ever fig. 38). But in a considerable number of individuals, the back end of the protoplasmic body was rounded off and separated by a marked interval from the pointed tip ; it seems that this may be a preliminary to cell-division, as all dividing individuals were found to have the protoplast rounded off in this way (cf. fig. 35). Many examples of division (from the presence of two pyrenoids in the cell up to the formation of two daughter-individuals, fig. 35) were observed ; in all cases such divisions were longitudinal and took place after withdrawal of the cilia. Curious division-stages were found in the form of very large individuals (in this case with or without cilia) containing a considerable number (eight or more) of protoplasmic units, each with a pyrenoid (fig. 36) ; such individuals may possibly have been forming gametes. The prominent beak at the point of origin of the cilia, described and figured by Wille, was often difficult to recognise. On the other hand, in a few cases there was a very pronounced development of this beak (fig. 40) in the form of a rounded protrusion, from the base of which the cilia arose. Apart from these peculiarities, the Antarctic form showed all the features described by Wille, viz. ribbing of the basin-shaped chloroplast, an elongated stigma (rarely visible), con- tractile vacuoles, etc. 2. CHLAMYDOMONAS EHRENBEKGII, Gorosck., Bull. Soc. imp. d. Nat. de Moscou, 1890, No. 3, p. 128-131, pi. iii., figs. 10-25. Samples 10 and 11, common. Probable zygowpores observed in sample 11. VOL. III. 16 122 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 3. ? CHLAMYDOMONAS INTERMEDIA, Chod., Alg. Suisse, 1902, p. 135. Samples 10 and 11, rather common. I am somewhat doubtful about the determination of this form. 4. CHLAMYDOMONAS NIVALIS (Sommerf.), Wille, Algol. Notizen, xi., Nyt Magazin f. Naturvidenskab, xli., 1903, pp. 147-148 (text fig. 1, A). Samples 4-6 (red snow !), common. Cf. description on p. 119; as suggested by Chodat, Wille, etc., these resting- cells may include Lagerheim's C. sanguined. Diam. of resting-cells = 10-20 M. TEXT FIGURE 1. A, Chlamydomonas niralis (Sommerf. ), Wille, resting-cells from the red snow (xllOO); B, Navicula muticopsis, V. Heurck, outline of an individual from sample 11 to show shape ( x 1030) ; C, Chlcninjdomonas, sp., resting-eells from the red snow (cf. p. 119) (xllOO); D, resting-cells from the yellow snow (cf. p. 118) (x830); E, upper figure, Microcystis merismopedioides, n. sp., surface-view of colony (cf. p. 130) (xllOO); lower figure, typical colony of the same ( x 540) ; F, Sphxrocystis schroeteri, Chod., f. nivalis, n. f. from the yellow snow ( x 540) ; G, the same, showing division of cells of colony ( x 830) ; H, Ccelastnim mieroporum, Naeg., f. irregulare, n. f. (cf. p. 126) ( x 1100). 5. CHLAMYDOMONAS, sp. (text fig. 1, C). Sample 4 (red snow !), rather common. Resting-cells in a wide sheath of mucilage ; diam. of cell alone = 9-10 mucilage = 20-28 M (see also pp. 119-120). of cell and PHACOTACE^. 6. PTEROMONAS NIVALIS (Shuttelw.), Chod., Alg. Suisse, 1902, p. 145, fig. 70 ; Wille, Algol. Notizen, xiii., Nyt Magazin f. Naturvidenskab, xli., 1903, p. 167-171, pi. iii., figs. 46-51 (PL I., figs. 22-24 and 31). FRESHWATER ALG^E OF THE SOUTH ORKNEYS. 123 Samples 1-3 (yellow snow!), isolated. This species should probably he transferred to the genus Scotiella (cf. pp. 109-111). Length of individuals = 'I'l M ; breadth = 12 /«. TETRASPORA CEsE. 7. SPH.EROCYSTIS SCHROETERI, Chod., Bull. Herbier JBoissier, v., 1897, p. 296, pi. ix. Forma nivalis, n. f. (text fig. 1, F-G ; PL II., phot. 2, 8 (cf. pp. 113-115)). Familiar microscopies forma paulo irregulariore quam in specie typica; cellulse ante divisionem reservant abundantiam adipis, qui invenitur in cellulis filialibus ; cellulse sunt saspe ellipsoidese. Diam. cell. = 7-12 M ; diam. cell. fil. = 2-3 M. Samples 1 and 3, especially common in the latter. PROTOCOCCACEM. 8. CHLOROSPH.BRA ANTARCTICA, n. sp. (PI. I., figs. 2-6 ; PI. II., phots. 1,3, 5, 6, (7). Cellulse aut magnse sphsericse singulse aut parvse, paulum angulares, in familias parvas consociatas ; cellular magnse et interdum cellulse parvse vagina mucosa ampla mimitjB ; membrana inodice incrassata, plerumque prasbentes duo strata ; chromatophora fere sphaarica cum foramine parvo in una parte ; adeps semper adest abuudans in cellulis ; paucas gran ul SB amylaceae plerumque adsunt. Propagatio per divisionem ; zoosporas non inveni. Diam. max. cellulas magnse = 43 M ; diam. min. cell, parvas = 7 M (omnes transitiones inter duas dimensioues) ; diam. cell, plerumque = 11 M-2 6 M ; diam. vaginse mucosse = 39-50 /u (cell. pertinentes = 26-28 M). Probably nearly allied to C. angulosa, Klebs. (cf. p. 104). Samples 1-3 (yellow snow !), very abundant. For full consideration, see pp. 103-104. 9. TROCHISCIA HYSTRIX (Reinsch), Hansg., Hedwigict, 1888, p. 129; Reinsch, Uber Acanthococcus, Ber. Deutscli. Bot. Ges., 1886, p. 241, tab. xi., fig, 25. Sample 10, rare; previously recorded from South Georgia (Reinsch). 10. TROCHISCIA RETICULARIS (-Reinsch), Hansg., Prodr. Algenflora v. Bohmen, ii., 1892, p. 241. Sample 10, rather common. A small form of this species ; diam. cell. = 10 M. 11. TROCHISCIA ANTARCTICA, n. sp. (PI. L, fig. 30). Cellulas spheericse solitaria? cum membrana crassa gelatinosa numerosis processibus cuneatis truncatis obtectae et junctis reticulo costarum ; chromatophorse ? ; cellulse cum cytoplasmate grauuloso, semper granulas amylaceas et interdum aliquautum adipis includente. Propagatio ? Diam. cell. = 10-13 M ; crassitude membranse = 2-3 M. 124 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Samples 1-3 (yellow snow !), fairly common. Probably nearly allied to T. reticularis (Reinsch), Hansg. For full consideration, see p. 116. 12. TROCHISCIA NIVALIS, Lagerh., Ber. Deutsch. Bot. Ges., x., 1892, p. 530, and pi. xxviii., fig. 23 (PI. L, fig. 29). Sample 11, rare. The individuals were rather smaller than those described by Lagerheim (diam. cell. = 10 fj.), but as in his form covered with very numerous minute spines; one (or more ?) pyrenoids were visible in every case. There appear to be several chloroplasts. 13. TROCHISCIA PACHYDERMA (Reinsch), Hansg., Hedwigia, 1888, p. 128; Reinsch, Uber Acanthococcus, Ber. Deutsch. Bot. Ges., 1886, p. 240, tat), xi., figs. 8-9. Samples 10 and 11, fairly common. SCENEDESMACEsE (seusu Oltmanns). 14. UOCYSTIS LACUSTRIS, Chad., Bull. Herbier Boissier, v., 1897, p. 296, and pi. x., fig. 1-7. Forma nivalis, n. f. (PI. I., figs. 27, 28). Poli cellularum rotundati vel acuti ; in cellula aliquantum adipis fiavi. Long. cell. = 13-15 M; lat. cell. = 9-10 M. Samples 1-3 (yellow snow !), rare. This form has been fully considered on pp. 112-113. 15. OOCYSTIS SOLITARIA, With: in Wittrock et Nordstedt, " Alg. aquse dulc. exsicc," No. 244, Bot. Notiser, 1879, p. 24 and fig. Sample 11, rare. Cells ellipsoidal in shape, with rounded ends ; membrane moderately thick, with apparently two layers, slightly thicker at the two ends of the cell ; cells generally solitary, but now and again to the number of about eight within a mother-cell. Fat generally present in the cell-contents. Length of cells = 16-20 M ; width = 13 M. 16. CHODATELLA BREVISPINA, n. sp. (PI. I., figs. 25, 26 ; PI. II., phots. 3, 5. Ch). Cellulse ellipsoidese plus miuusve complauatee setis brevibus quje non amplius bis crassitudine membranse cellules exstaut per totam superficiem externam confertee ; setse plerumque tenues et angustse, interdum paulo crassiores, sequilonga3 ; inter ea quse cellula continet semper est adeps, plerumque abundans, ssepe similis duobus globis in utroque fine cellulse. Long. cell. = 17-20 ^ ; lat. cell. = 10-15 M. Samples 1 and 3 (yellow snow !), common ; isolated in sample 10. This species differs from all hitherto described species of Chodatella in having very short spines, which cover the surface uniformly. A full consideration will be found on pp. 111-112. FRESHWATER A.LGJE OF THE SOUTH ORKNEYS. 125 SCOTEELLA, nov. gen. Celluho ellipsoidcaj in utroque fine rotundatiu processibus aUeformibus plus minusve longitudinalibus sex aut multis munitje ; alse sunt aut rectse aut undulatse; chroma- tophoram singularein esse probabile est, cum pyrenoide ; abimdantia est adipis in una specie. Propagatio subdivisione cellulas imrnutatte aut sporaa perdunmtis in paucas partcs verisimilc est. Sporte perdurantes cum membranis valde incrassatis trans- figuratione cellularum vulgarium formari videntur. This genus is certainly a close ally of Oocystis (<;/.' p. 108). I think it very probable that Pt<>>\»uonas itivalis (Shuttlw.), Choc!., is a species of this genus (cf. p. ] 10). 17. SCOTIELLA ANTARCTICA, n. sp. (PI. I., figs. 7-17 ; PI. II., phots. 1, 4, 6, Sc). Cellule ellipsoidese circiter duplo longiores quam sunt latse sex e pariete exstantibus alseformibus processibus, qui extenduntur recti et sequidistantes inter duos fines cellula; instruct*. Unus par alarum oppositarum (alte principales) extenditur continuus circa cellulam ; duo alii pares alarum (alee laterales) separati sunt alis principalibus, et ab utroque fine celluhB paulum exstautes introrsum subito curvantur, ita ut in utroque fine cellulre sinus formatus esse videatur (cf. fig. 8 et 9). Ala quseque habet mediam incisuram propriam speciei. Cellula continet multum adipis flaventis ; cytoplasmatis structura investigari non potest. Sporas perdurantes cum membrana crassa et undulata sunt formats metamorphosi cellularum vulgarium. Propagatio (?) subdivisione celluhe immutata3 aut sporas perdurantis in paucas partes possibile videtur. Long. cell, ab altero fine ad alterum = 43-49 /« (interdum 55 M) ; lat. veri corporis cell. = 16-21 M; lat. totius cell. (i.e. cum alis) = 28-30 M (interdum 42 M). Samples 1-3 (yellow snow!), 5 and 6 (red snow!), 9, 11, and 15 ; rather common in yellow and red snow, rare in the other samples. Largest individuals in red snow. A full description and consideration of.this species will be found on pp. 105-108. 18. SCOTIELLA POLYPTERA, n. sp. (PI. I., figs. 18-21). Cellulse late ellipsoidea?, paulo longiores quam sunt latee, magno numero alarum multo minus exstantium quam in S. antarctica instruct*. Alse plerumque sunt paulum directee in spiram et undulatse, ita ut adumbratio cellulse videatur crenata ab omnibus partibus. Alse exstant paulum ab utroque fine cellulse et curvantur introrsum ita ut sinus debilis formetur. Adeps reservari non videtur. Sporse per- durantes ? Propagatio subdivisione cellularum vulgarium probabilis est. Long. cell. = 20-24 /u ; lat, cell. = 16-17 M. Samples 1 and 3 (yellow snow !), very rare ; as an occasional form in samples 10, 11, and 15. This species has been considered more fully on pp. 108-109. 19. ? RAPHIDIUM PYRENOGERUM, Chod., Algues vertes de la Suisse, 1902, p. 200, fig. 119 (PL I., fig. 34). Samples 1 and 3 (yellow snow !), rare. 126 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. Cf. p. 117. The forms observed are possibly referable to a distinct species, but the material was insufficient to come to definite conclusions on this point. Width of cells = 2 M. 20. CCELASTRUM MICROPORUM, Naeg. ex. A. Br., Alg. unicell., 1885, p. 70 ; Rabenh., Fl Europ. Alg., iii., 1868, p. 80. Samples 10, 11, and 15, fairly common. Forma irregulare, n. f. (text fig. 1, H, p. 122). Cellules coenobii irregularissime cohserentes. Iii sample 11 there occurred side by side with normal colonies of C. microporum others, in which the cells were very irregularly connected, so that the compact spherical appearance of the normal colony was often quite lost. Frequently the sphere was only half formed ; in other cases, while several cells of the colony showed the usual arrange- ment, others were so disposed that they stood off from the general surface of the colony and completely destroyed the symmetrical character of the latter (fig. 1, H). In other cases again the colonies were very small, consisting of only four or six cells. These peculiar forms may possibly be explained by Senn's observations (" fiber einige colouie- bildeude einzellige Algen," Bot. Zeitung, Ivii., 1899), who found that colonies of Caslastrum tend to dissociate into their individual cells if plenty of oxygen is present in the surrounding medium. This is likely to be the case in water in these Antarctic localities and may account for the numerous irregularities above described. Samples 10, 11, and 14 contained numerous isolated cells of the Ccelastrum-type, and these are very probably to be regarded as dissociation-products of normal colonies. 21. CCELASTRUM SPH^RICUM, Naeg., Gatt. einzell. Algen, Zurich, 1849, p. 98, and tab. v., c, fig. 1. Sample 11, rather rare. P LEV 'ROCOCO 'AC 'E^E. 22. PLEUROCOCCUS VULGARIS, Menegh., Monograph. Nostoch., p. 38. Samples 1 and 3 (yellow snow !), rare; samples 10 and 11, not uncommon. This species was occasionally found in Nos. 10 and 11 forming short filaments. 23. PROTODERMA BROWNII, n. sp. (PI. I., fig. 1 ; PI. II., phots. 1, 2, 3, 5, P). Thallus constat ex uno vel duobus (vel pluribus ?) stratis cellularum et explanatus est in summa nive ; margo thalli irregularis. Cellulee multangulares vel angulis modice rotundatis ; membranse cellularurn gelatinosse (?), hyalinte, larnellosas, lamella intermedia paulum granulata. Chromatophora singula, similis disco arcuato, cum pyrenoide. Cellulse interdum continent aliquantum adipis. Propagatio ? Diana, cell. = 5-12 M. Samples 1 and 3 (yellow snow !), abundant. It is probable that Pleurococcus vulgaris, Men. /3 coheerens, Wittr. (" Om snb'ns och isens Flora," loc. cit.), in part belongs to this species. Wittrock's fig. 17 (on pi. iii.) strongly recalls a patch of Protoderma brownii. FRESHWATER ALG.E OF THE SOUTH ORKNEYS. 127 A full consideration of this species will be found on pp. 102-103. In sample 16 a very similar form was found growing on Prasiola crispa ; the cells (cliam. 5-7 p.), how- ever, lacked fat, and the cell-walls were not nearly so gelatinous. 24. EREMOSPH^RA VIRIDIS, De Bary, Conj., p. 56, tab. viii., fig?. 26-27; Rabenl., FL Europ. Alg., iii., 1868, p. '24. Sample 11. Average diameter of cells = 50 M. ULOTRWHACE^E. 25. ULOTHRIX SUBTILIS, Kiitz., Spec. Alg., p. 345 ; Tab. Phyc., ii., tab. 85 ; Rabenh., FL Europ. Alg., iii., 1868, p. 365 (PI. II., phots. 1, 2, 6, U). Samples 1 and 3 (yellow snow !), rather rare. CHJETOPHORA CE;E. 26. RAPHIDONEMA NIVALE, Lagerh., Ber. Deutsch. Bot. Ges., x., 1892, p. 523, pi. xxviii., figs. 15-21 (PI. I., figs. 32, 33). Samples 1-3 (yellow snow !), rather rare ; 4-6 (red snow !), rather common. Many of the filaments were narrower than Lagerheim's form ; diara. of cells = 2-4 //. See also pp. 116-117. (EDOGONIACE^:. 27. (EDOGONIUM, sp. Samples 1 and 3 (yellow snow !), isolated. Diam. of cells = 20 p. ; length of cells = 56-65 M ; cells with numerous caps. 28. (EDOGONIUM, sp. Sample 4 (red snow !), isolated. Diam. cell. = 8 // ; cells about three times as long as their diameter. PRASIOLACEM 29. PRASIOLA CRISPA (Lightf.), Ay., Sp., p. 416; Kiitz., Tab. Phyc., v., tab. 40, fig. 6. Samples 8, 9, 11, 12, and 16, abundant; numerous early stages in sample 16. This form is already well known as occurring in Antarctic regions. It was first recorded by Hooker and Harvey (Botany of the Antarctic Voyage (Flora Antarctica), vol. ii., pp. 498-499). as Ulva crispa, Lightf., as occurring in " Berkeley Sound, Falkland Islands ; on moist rocks ; Cockburn Island, Graham's Land ; very abundant." They add the comment : " A highly interesting species, because it is one of the very few ter- restrial plants that have been gathered on the limits of vegetation both in the Northern and Southern hemisphere." Subsequently it was recorded by Hariot from Cape Horn, 128 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. by Svedelius from Patagonia, and by Wille from Cape Adare (" Antarktische Algen. Mitteilungen liber einige von C. E. Borchgrevink auf dem antarktischen Festlande gesam- melte Pflanzen," Nyt Magazin f. Naturvidenskab, xl., 1902, pp. 209-219). Various authors, who have dealt with the Antarctic Prasiotas, have held rather different views as to the specific determinations ; several (such as Kiitzing, Rabenhorst, and Svedelius) con- sider that there are two species, Prasiola crispa and Prasiola antarctica, Kiitz.1 These different views are fully considered in the paper of Wille above cited. On the basis of a careful investigation of Borchgrevink's material from Cape Adare, Wille (loc. cit., p. 217) comes to the conclusion that there is no true point of difference between P. antarctica and P. crispa ; it appears, however, that Borchgrevink's material was the true P. crispa and not the form described as P. antarctica by other authorities. There appears to be no doubt that some of the Antarctic Prasiola is distinguished from the normal P. crispa by larger interspaces between the areolae and prominent thickening of the outer walls of the cells, but it may be questioned whether they warrant the establishment of a distinct species. The differences do not appear to be of specific value, and the case would perhaps be best met by regarding the Antarctic type as a var. antarctica of P. crispa. No typical specimens of P. antarctica were present in the material from the South Orkneys.2 My material showed most of the stages figured by Wille on his pi. iii. Numerous filaments of the Hormidium-stage were observed, but in many of them a considerable number of the cells were dead or dying, and it appeared that the filaments were under- going fragmentation without coming to anything further. Stages like those shown in Wille's figs. 13 and 14 were also not uncommon. Little detached groups of cells, like those of Wille's figs. 11 and 12 were very common in the sediment at the bottom of the tubes. It appears that such groups of cells are not necessarily formed only in the marginal portions of the thallus. In some specimens there were extensive strips of the thallus in which the cells were obviously in a moribund condition, and in the centre of such patches there was often a small rounded group of living cells with very abundant contents. The surrounding dying cells were of considerably larger dimensions than the others, and looked as though they had not divided recently. No doubt the central group of living cells becomes freed by the dying away of the surrounding part of the thallus, and acts as an organ of vegetative propagation. The cells of the South Orkneys material had a curious purplish or olive-brown tinge, which is probably due to the action of the preservative (1 per cent, phenol) ; staining with iodine brought out the chloroplast and pyrenoid very plainly. The dimensions were as follows : — width of cells = 4 M ; length = 6 M ; thickness (i.e. dimensions at right angles to surface of thallus) = 13 M. There was always only a single layer of cells. 1 Of. also W. and G. S. West, Brit. Antarct. Exped., 1907-09, vol. i., Biology, part vii., "Freshwater Algse," 1911, p. 272-274. - Since writing the report on the Algre of the South Orkneys, which was published in the Journ. Linn. Sin:, 1 have examined the true Prasiola antarctica, and this has consequently led me to modify slightly my remarks on the two species given in the Linn. Soc. paper. FRESHWATER ALG.-E OF THE SOUTH ORKNEYS. 129 B. CONJUGATE. MESOT^ENIA CE&. 30. MESOT/ENIUM ENDLICHERIANUM, Naeg., Gatt. einzell. Alg., 1849, p. 109, tab. G, B ; West and West, Brit. Desm., 1904, p. 56, pi. iv., figs. 20, 21. Sample 15, fairly common ; samples 1 and 3 (yellow snow !), isolated. There appeared to be more than two pyrenoids. Cells 24-26 M long ; 8-9 n broad. 31. CYLINDROCYSTIS BREBISSONII, Menegh., Monograph. Nostocli., 1842, p. 89, tab. xii., fig. 13; West and West, Brit. Desm., 1904, p. 58, pi. iv., figs. 23-32. Sample 8, fairly common ; previously recorded from South Georgia (Reinsch). Two elongated pyreuoids mostly very obvious; length of cells = 50-54 M ; breadth = 1 3 M. 32. CYLINDROCYSTIS CRASSA, De Bary, Conj., 1858, pp. 37, 74, tab. vii., fig. c, 1-2 ; West and West, Brit. Desm., 1904, p. 59, pi. iv., figs. 33-38. Samples 8 and 9, fairly common. Cells 32-35 ^ long; 14-1 5 M broad. Two rounded pyreuoids. Cells occasionally very slightly curved, with broadly rounded ends. ZYGNEMAGEM. 33. MOUGEOTIA, sp. Sample 8 ; only one filament of four cells seen. Cells 3 1 /UL broad ; six times as long. 34. ZYGNEMA, sp. Sample 4 (red snow !) ; one very much shrunken filament of about twenty cells. Diam. cell. = 28 M; cells of the same length or one and a half times as long as broad. C. HETEROKONT^E. CONFERVACEjE. 35. CONFERVA BOMBYCINA, Ag., Syst., p. 83, n. 10; Rabenh., Fl. Europ. Alg., iii., 1868, p. 323. Forma minor, Wille, Algol. Mitteil., Pringsli. Jahrb., xviii., p. 467. Samples 8, 9, 10, and 15, rather rare. Diam. cell — 6 M ; two to three times as long. D. CYANOPHYCEyE (Myxophycea). CHROOOOCOAGE^:. 36. SYNKCHOCOCCUS ^RUGINOSUS, Naeg., Gatt. einzell. Alg., 1849, p. 56, tab. 1, E., fig. 1. Sample 10, rather rare. Cells isolated or in twos ; diam. cell = 3 M VOL. III. 17 130 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 37. ENTOPHYSALIS GRANTJLOSA, Kiitz., Pliyc. gen., 1843, p. 177, pi. xviii., fig. 5. Sample 16, common. 38. ? APHANOTHECE SAXICOLA, Naeg., Gatt. einzell. Alg., 1849, p. 60, tab. 1, H, fig. 2. Sample 1 1 , rare. 39. MICROCYSTIS OLIVACEA, Kiitz., Phyc. gen., p. 170; Rabenh., Fl. Europ. Alg., ii., 1865, p. 51. Samples 8, 9, 10, 11, and 14, rather common; previously recorded from Kerguelen (Reinsch). 40. MICROCYSTIS MERISMOPEDIOIDES, n. sp. (text fig. 1, E, p. 122). Familise parvae solidse circumferentia ii-regulari constant ex cellulis pusillis quas muco fusco-flavescente vel rarius achroo et, ut videtur, tenaci cohaerent. Cellulse in facie familise quaternaries regularissime disposita? (ut in genere Merismopedia) ; dispositio cellularum in partibus interioribus familise iuvestigari non potest, sed dispositio regularis verisimile est. Diam. fam. = 13-20/" ; diam. cell, fere 0'7 M. Samples 11 and 14, common. In view of the very minute size of the cells and their dense aggregation, it has been impossible to determine exactly their arrangement in the interior of the solid colonies, but focussing in different planes seems to show that the same regular arrangement obtains all through. It is possible that this species belongs to the genus Eucapsis, described by Clements and Shantz (Minnesota Bot. Studies, iv., 1909, p. 134), but in the latter genus the colonies are described as cubical, which in no way applies to the rather irregular colonies of M. merismopedioides. They closely resemble those of a Microcystis in all except the regular arrangement of the minute cells. 41. CLATHROCYSTIS RETICULATA (Lcmm.), Forti, Sylloge Myxopltycearum, 1907, p. 96. Sample 10, rather rare. 42. GOMPHOSPH^RIA APONINA, Kutz., Tab. Phyc., i., tab. xxxi., fig. 3 ; Rabenh., Fl. Europ. Alg., ii., 1865, p. 56. Sample 11, rare. 43. CCELOSPH^ERIUM KUTZINGIANUM, Naeg., Gatt. einzell. Alg., 1849, p. 54, tab. 1, c. Sample 11, rare. 44. MERISMOPEDIA GLAUCUM (Ehrb.), Naeg., Gatt. einzell. Alg., 1849, p. 55, tab. 1, D, fig. 1. Sample 1 1 , rather rare. 45. MERISMOPEDIA TENUISSIMUM, Lemm., Beitr. z. Kenntn. d. Planktonalgen, Bot. Centralbl., 1898, p. 154. Sample 10, rare. FRESHWATER ALG^E OF THE SOUTH ORKNEYS. 131 OSC1LLA TORI A CE^E. 46. OSCILLATORIA BREVis, Kiitz. ; Gomont, Oscillariees, Ann. Sci. Nat., Sot., xvi., p. 249, pi. vii.,figs. 14-15. Sample 10, rather rare. 47. OSCILLATORIA SPLENDIDA, Grev. ; Gomont, Oscillariees, Ann. Sci. Nat., Bot., xvi., p. '244, pi. vii., figs. 7-8. Sample 10, rather rare. 48. OSCILLATORIA SUBTILISSIMA, Kiitz., Tab. Phyc., i., 1845-49, p. 27, tab. xxxviii., fig. 7. Sample 10, rather rare. 49. OSCILLATORIA TENUIS, Ag. ; Gomont, Oscillariees, Ann. Sci. Nat., Bot., xvi., p. 240, pi. vii., figs. 2, 3. Samples 10. 11, and 15, rather rare. Forma sordida, Kiitz., was also present. 50. SPIRULINA SUBTILISSIMA, Kiitz., Phyc. gen., 1843, p. 183 ; Rabenh., Fl. Europ. Alg., ii., 1865, p. 93; Gomont, Oscillariees, p. 272, pi. vii., fig. 30. Sample 10, rather common. NOSTOOAOE2E. 51. ISOCYSTIS INFUSIONUM (Kiitz.), Borzi, Nuov. giorn. hot. ital., x., 1878, p. 468. Samples 8, 11, 13, 15, and 17, rather common. 52. NOSTOC MINUTISSIMUM, Kiitz., Phyc. gen., p. 204 ; Rabenh., FL Europ. Alg., ii., 1865, p. 162. Samples 10 and 11, rather common ; 1 and 3 (yellow snow !), rare. RIVULARIACE^E. 53. CALOTHRIX ^RUGINEA, Thuret ; Bornet et Flahault, Nostocacees heterocystees, 1886-88, p. 358. Sample 1 4, isolated. Diam. cell =9-11 M. Only one group of filaments was seen, and the determination is therefore somewhat doubtful. C. seruginea is a marine form, but the habitat from which sample 14 came would be likely to harbour marine forms. E. DIATOMACE^E (Bacillarieje). 54. MELOSIRA VARIANS, Ag., Consp., 1830, p. 64; Rabenh., Fl. Europ. Alg., i. 1864, p. 40. Sample 9, rather rare. 132 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 55. MELOSIRA SOL, Kiltz. ; Van Heurck, Atlas, pi. xci., figs. 7-9. Sample 4 (red snow !) ; one short chain seen (living) ; previously recorded from the Antarctic (Hooker and Harvey). 56. COSCINODISCUS RADIATUS, Ehrb. (1838); Rabenh., Fl. Europ. Alg., i., 1864, p. 34. Samples 4 and 6 (red snow!), isolated ; previously recorded from Kerguelen (Hooker and Harvey). A small form (diam. valve = 40-60 M), otherwise agreeing with the existing descriptions. 57. TRICERATIUM, sp. Sample 4 (red snow !) ; only a single dead individual seen, but fragments of the valves common. The single individual seen closely resembled Van Heurck's (Atlas, pi. cxii., fig. 1) and Wolle's (Diatomacese of North America, pi. cv., fig. 8) figures of T. arcticum, Bright, in the character of the areolse (small at the three corners !) ; the general shape was more that of T. repletum, Grev., var. balearica, Grim. (Van Heurck, Atlas, pi. ex., fig. 7). 58. SYNREDRA, sp. Sample 11, rare. 59. EUNOTIA GRACILIS, W. Smith, Brit. Dial., i., 1853, p. 16, and pi. xxx., fig. 249. Sample 9, rather common. A form with but very slightly recurved ends ; length of valve = 22 M ; breadth = 2 /j.. 60. COCCONEIS COSTATA, Greg., Trans. Micr. Journ., v., p. 68, pi. i., fig. 27. Samples 9 and 10, rare. 61. NAVICULA BOREALIS (Ehrb.), Kiltz. ; Van Heurck, Synopsis Diat., 1885, p. 76, pi. vi., fig. 3. Samples 4 (rare), 9, 13, and 17, rather common ; previously recorded from Cockburn Island (Hooker and Harvey). Length of valve 35-58 M ; breadth 8-11 M. 62. NAVICULA BRAUNII, Grim. ; Van Heurck, Synopsis Diat., 1885, p. 79, pi. vi., fig. 21. Sample 10, very rare. Length of valve = 37 /« ; breadth = 12 n. 63. NAVICULA BREBISSONII, Kiltz., var. DIMINUTA, Van Heurck, Synopsis Diat., 1885, p. 77, pi. v., fig. 8. Samples 9, 10, 13, and 15, rather common. Length of valve = 20-34 n (rarely 45-47 M) ; breadth = 5-7 M. SCOT. NAT. ANT. EXP. FRESHWATER ALGAE — FRITSCH I. VOL. III. M'Farlane fit Ersklne, Eciir SCOT. NAT. ANT. EXP. FRESHWATER ALGAE — FRITSCH II. VOL. III. /-; • . m c ••--< chg X ch M'Farlane fr Erskin FRESHWATER ALU.E OK THE SOUTH ORKNEYS. 133 64. NAVICULA MUTICOPSIS, Van Heurck, Diatomees, Result, voyage du s.y. " Belgica," Anvers, 1909, p. 12, tub. 2, fig. 181 (text fig. 1, B, p. 122). Samples 8, 9, 10, 11, and 15, common ; previously recorded from the Antarctic (Van Heurck, Messrs West). Length of valve = 21-24 M ; breadth (at widest point) = 10 /u. In most of the individuals the sides were quite fiat, but in others they were somewhat arched ; ends pronouncedly swollen in a capitate manner. Such capitate forms approach jV. dicephala (Ehrb.), W. Smith. 65. ? NAVICULA LUCIDULA, Grun. • Van Heurck, Atlas, 1880-81, pi. xiv., fig. 40. Sample 9, rather rare. Certainly a very close ally of this species. 66. NAVICULA MUTICA, Ktitz. ; Van Heurck, Syno2)sis Diat., 1885, p. 95, pi. x., fig. 17. Samples 8, 9, 10, 13, and 17, common; previously recorded from the Antarctic (Reiusch, Holmboe). Length of valve = 16-35 M ; breadth = 7-11 M (incl. f. Goppertiana, Bleisch). 67. AMPHORA OVALIS, Kiitz. ; Van Heurck, Synopsis Diat., 1885, p. 59, pi. i., fig. 1. Sample 4 (red snow !), isolated ; the var. gracilis has previously been recorded from Kergueleu (Reiusch). 68. GOMPHONEMA MONTANUM, Schum. ; Van Heurck, Synopsis Diat., 1885, p. 124, pi. xxiii., figs. 33 and 36. Sample 9, isolated specimens. EXPLANATION OF THE PLATES. PLATE I. Fig. 1. Protoderma brownii, n. sp. — A small portion of one of the sheets of cells formed by this species ( x 830). Figs. 2-6. Chlorosphxra antarctica, n. sp. — Fig. 2. Large isolated cell with a wide mucilage-sheath and a quantity of fat in the cell-contents ( x 540). Fig. 3. A group of small cells without mucilage-sheath ; fat equally diffused through the contents (xllOO). Figs. 4-5. Oval cells with segregated masses of fat; possibly a stage in which the cells are preparing to divide (cf. p. 104) ( x 830, 730 respectively). Fig. 6. A cell in which the fat is very prominently developed ( x 540). Figs. 7-11. Scotiella antarctica, n. sp. — 1-2 = principal wings; 3-4 and 5-6 = the two pairs of lateral wings; pw = principal wings. Fig. 7. A rather small normal individual, as seen when the principal wings are parallel to the substratum ( x 830). Figs. 8, 9. Two oblique end-views of the organism to show the course of the wings ( x 830). Fig. 10. Part of a normal individual in which the principal wings are inclined to the substratum ( x 540). Fig. 11. An individual seen in optical section ( x 430). Figs. 12-16. Scotiella antarctica, n. sp. — Stages in formation of resting-spores (1). Fig. 12. An individual in which the wings have lost in definition ( x 540). Figs. 13, 14, 15. Three stages in the o° * iln *.//. " Belgica" (1897-99), Arivers, 1903. WBKTH, E., "Die Vegetation der Subantarktischen Inseln," Deutvhr Xiiolar-Exp. (1901-03), Bd. viii. 1, He i-l in, 1906. WEST, \V. and G. S., "Freshwater Alga'," /iritia/i Antarctic, Expedition (1907-09): Reports on the Scientific Investigations, i., vii., London, 1912. WIMIEMAN, E., " Les Phanerogames des Terres inagellaniques," lien, du voyayc du a.y. " Belyica," Anvers, 1905. WRIGHT, C. H., " The Botany of Gough Island : Hepatics and Fungi," Journ. Linn. Soc. Lond., Bot., xxxvii., 1905, p. 265. ZAHLBRUCKNER, A., "Die Flechten," Deutsche SililpoJar-Erp. (1901-03), Bd. viii. 1, Berlin, 1906. PRINTED BY NRIU. AND CO., LTD., KDINBDROH VOL. III. 20