Aj Wie iv } 4 , Vous A ld * DUPLICATA DE LA peciiee | pu CONSERVAT CINE BCCATICUE } VERDO EN 1922 I TRANSACTIONS AND PROCEEDINGS OF THE | BOTANICAL SOCIETY OF EDINBURGH. VOLUME XXV. 5a ray dated. DUPLICATA DE LA BIBLIOTHEQUE © 1) DU CONSERVATCINE ECTALIQUE DE GENEVE VENDU EN 1922 A a ; & ad at ees ree ve = meer yt green PEDRO OL EDINBURGH: PRINTED FOR THE BOTANICAL SOCIETY BY NEILL & CO., LIMITED. | And to be obtained from the SECRETARY OF THE SOCIETY, 1910. ie) Yc fe a es us 4e 42 AA ek 3) \\ be, We Sh DUPLICAT) DE I, A \ BIB BG a SOUR DU Consrr yy; — = ¢ TRANSACTIONS AND PROCEEDINGS OF THE BOTANICAL SOCIETY OF EDINBURGH. VOLUME XXV. LIGRARY NEW YORK BOTANKAL GARBEN DUPLICATA DE LA BIBLIOTHEQUEC DU CONSERVATCICE BOTANIQUE DE GENEVE VENDU EN 1922 EDINBURGH : PRINTED FOR THE BOTANICAL SOCIETY. MDCCCCX rat fi Kae nyo /9/ PRINTED BY NEILL AND CO,, LTD., EDINBURGH THE DISTRIBUTION OF HEPATICA IN SCOTLAND BY SYMERS M. MACVICAR 7 PREFATORY NOTE THis work may be regarded as a new departure for Scotland in this branch of botany. The distribution of Hepaticew in Scotland, as in England and Wales, has hitherto been given only in fragmentary form. Only an increasing interest in the study, and the accumulation of a large amount of material and information, have rendered a more detailed distribution possible. For some years there has been an awakening of interest in the study of the Hepatice of the British Isles. The Moss Exchange Club, initiated fifteen years ago, and various publications, have stimulated this interest, and it is hoped that the issue of this volume will give a further impetus in this direction. In 1904 there appeared a paper by the author in the Annals of Scottish Natural History, entitled a “Census of Scottish Hepatice.” This was followed at intervals by other papers giving additions to the Census. Scotland is peculiarly rich in these plants, and several Scottish botanists have given attention to them. The discoveries of rare species have also attracted some English botanists, who have assisted by collecting in various parts of the country. The author has been investigating the flora for several years, with a view to the presentation of the facts set forth in the following pages. Hitherto the distribution has been given by counties only, these having been distinguished by numbers. The present work gives the localities, with the collectors’ names, of the older botanists whose specimens have been available for examination, as well as those of recent date. A few records have been taken from literature, but they have Vi Nal PREFATORY NOTE been almost confined to works by specialists on the subject, and each of these records is indicated by a special mark in the context, as the specimens upon which they were founded have not been examined by the author, as have all the others with the exception of five or six which are marked “in litt.” The author wishes to thank all those botanists who have sent plants for examination, also those who have afforded opportunities for the inspection of Herbaria. INVERMOIDART, ACHARACLE, ARGYLL, August 1910. AUG 7= 1923 THE mist RIBUTION OF HEPATIC IN SCOTLAND LMRARY NIT WY Y Ome ik BOTANECA HISTORICAL GAR SEN THE first author who appears to have mentioned Scottish Hepatice is Str Rospert SIBBALD (1641-1722). In his Scotia Illustrata, 1684, he gives Marchantia polymorpha! and Pellia epiphylla, also another thalloid species of which the identity is doubtful, and Plagiochila asplenioides. Nearly a hundred years later, in 1772, the REv. JoHn LigHtTrooT (1735-88) travelled through Scotland with Pennant, and gave the botanical results of the tour in his Flora Scotica, 1777. In this work the following additional Hepatice are given:—Riccia glawea?, Targionia hypo- phylla, Preissia quadrata, Conocephalum conicum, Anewra pinguis, Metzgeria furcata, Blasia pusilla, Gymnomitrium concinnatum, Lophocolea bidentata?, Chiloscyphus poly- anthos, Cephalozia bicuspidata, Calypogeia Trichomanis, CO. fissa, Lepidozia reptans, Anthelia julacea, Diplo- phyllum albicans, Radula complanata, Plewrozia pur- purea, Madotheca platyphylla, Frullania Tamarisci, and F. dilatata. His Jungermannia lanceolata, J. viticulosa, J. quinquedentata, J. undulata, and J. reswpinata are too uncertain to identify. With his Plewrozia purpurea he has confused Scapania purpwrascens, as can be seen from the habitats given. This mistake has also been made by more recent botanists. JAMES Dickson (1738-1822) made numerous additions to the British Jungermannie, according to Hooker. He published the Fase. Plant. Crypt. Brit., 1-4, in 1785-1801. 1 The modern names are here used. TRANS. BOT. SOC. EDIN. VOL. XXV. if 2 THE DISTRIBUTION OF HEPATIC IN SCOTLAND His additions to the Hepatice of Scotland appear to have been Anewra multifida ?, Marsupella emarginata, Haplozia cordifolia, Sphenolobus minutus, Plagiochila spinulosa, Nowellia curvifolia, Chandonanthus setiformis, Herberta adunca, Ptilidium ciliare, and Trichocolea tomentella. His Anthoceros multifidus is most probably Anewra multi- fida as Hooker supposes, although Withering received specimens from Dickson and considered the plant to be an Anthoceros. The habitat “crevices of rocks in the High- lands” would suit the common Scottish form, Anewra multifida var. ambrosioides, with which it is probable that Withering was not familiar; it would not suit Antho- ceros. Regarding Dickson’s Riccia spwria and Junger- mannia Thuja, Mitten made the following note in 1906 in a copy of the Census Catalogue of British Hepatice im reference to the J. Thuja: “A specimen of Dickson’s was sent to him by Menzies and is the N.W. American species. It was not Dickson’s way to care about localities; thus he placed in ‘Alp. Scot.’ as a sort of refuge for anything he had forgotten, suchas .... andthe Malayan Carpolipwm spurvum, his Riccia, with the figure of which there is no fault to find.” ARCHIBALD MENZIES (1754-1842) added Pellia endivie- folia and Madotheca Thuja ? GEORGE Don (1764-1814) added Anastrophyllum Doni- anum, Harpanthus scutatus, and Scapania ornithopodi- odes. CHARLES LYELL (1767-1849) appears to have been the first who found the following in Scotland :—Pallavicinia hibernica, P. Flotowiana, Haplomitrium Hookeri, Nardia hyalina, Haplozia crenulata, Lophozia Muelleri, L. excisa, L. gracilis, Leptocyphus anomalus, Cephalozia Franeisci, Saccogyna viticulosa, Scapania compacta, and Lejewnea cavifolia. THOMAS Drummond (d. 1835) added Gymnonitriwm obtusum, Jamesoniella autumnalis var. Schaderi, Lophozia ulpestris var. gelida, Sphenolobus Kunzeanus, Cepha- lnziclla stellulifera, and Scapania subalpina. THOMAS Hopkirk (1785-1841), the author of Flora Glottiana, 1818, added Lophozia incisu and Diplophyllum obtus ifol VL NN. HISTORICAL ] Srr WILLIAM JACKSON HOOKER (1785-1855). A new era in the study of Hepatice was inaugurated when the British Jungermannie was published in 1812-16—the date of each part is given by A. Gepp in Journal of Botany, 1906, p. 177. His Flora Scotica was published in 1821. I gather that Hooker added the following to our flora:—Metzgeria pubescens, Haplozia sphwrocarpa var. lurida, Anastrepta orcadensis, Leptocyphus Taylori, Cephaloziella byssacea?, Bazzania trilobata, B. triangu- luris, Plewroclada albescens, Blepharostoma trichophyllum, Scapania umbrosa, Madotheca levigata, and Cololejewnea calcared. Robert KAYE GREVILLE (1794-1866) published his Flora Edinensis in 1824. In this work the only hepatic not mentioned in Hooker’s Flora Scotica is Haplozia crenulata var. gracillima. He added to the flora of Scotland, besides this variety, Riccia fluitans, Reboulia hemispherica, Metzgeria conjugata, M. hamata, Gymno- mitriwm corallioides, Jamesoniella Carrington, Lophozia eylindracea, Sphenolobus saxicolus, Cephalozia lunule- Folia, Mastigophora Woodsvi, Seapania cwrta, Marchesinia Mackau, Frullania microphylla, and F. germana. Davin Don (1799-1841) appears to have added Odonto- schisma Sphagni. GEORGE A. WALKER-ARNOTT (1799-1866), Professor of Botany, Glasgow, does not seem to have made any addi- tions to our flora, but I have not had the opportunity of examining his herbarium. WILLIAM WILSON (1799-1871), the author of Bryologica Britannica, 1855, appears to have added Plagiochila tridenticulata. JOHN Hurron Batrour (1808-84), Professor of Botany, Edinburgh, who made numerous botanical expeditions over the greater part of Scotland, did not, unfortunately for our subject, make a special study of Hepatice. Hence his only addition to our list appears to be Anthelia Juratzkana, He included a short list of hepaties in Trans. Bot. Soc. Ed., vol. i., in a catalogue of plants gathered in the Outer Hebrides in 1841. ALEXANDER CROALL (1809-85) collected in many parts of Scotland. His additions to the flora are:—Riccia Les- 4 THE DISTRIBUTION OF HEPATIC IN SCOTLAND curianda, Nardia obovata, Cephalozia fluitans, Lepidozia Pearsoni, Diplophyllum taxifolium, Scapania Bartlingii, S. wquiloba, S. aspera, S. uliginosa, S. paludosa, and Radula Lindbergii. WILLIAM GARDINER (1809 ?-52), author of Flora of Forfur, 1848, collected principally in the north-east of the country. I cannot find that he added any species to our flora except perhaps Lophozia lycopodioides. CHARLES Howie (1811-99) collected mainly in Fife. He visited West Ross-shire in 1867 in company with Charles Jenner, when he found some interesting Hepatice, but he does not appear to have added any species to our flora. GEORGE Dickie (1812-82), Professor of Botany, Aber- deen, the author of Botanist’s Guide to Aberdeen, 1860, added Anthoceros punctatus probably, and Hygrobiella laxifolia. JAMES CRUICKSHANK (ca. 1813-47) published a list of Jungermannie from the neighbourhood of Dumfries, in the Phytologist, 1842. He collected in various parts of Scot- land, and added Lophozia bicrenata and Pallavicinia Lyellir ? Robert MACKENZIE STARK (1815-73), the author of Popular History of British Mosses, 1858, added Lepidozia prrnata. WILLIAM GOURLIE (1815-56) was the discoverer of Jubula Hutchinsic in Scotland. GEORGE JASPER Lyon (1816-62) made the additions :— Lophozia turbinata, Lophocolea heterophylla, Cephalozia connivens, Colwrolejewnea calyptrifolia, Microlejeunea uwlicina, and Lejewnea patens ? Mr ApamMson, of whom no particulars are available, first found Plewroclada albescens var. islandica in Scotland. WiLLIAM WILSON Evans (1820-85) added Pallavicinia Blyttii. PETER GRAY (1818-99) appears to have added Foss- ombronia pusilla and Scapania irrigua. ALEXANDER OsmMoND BLACK (d. 1864) discovered Gym- nomitriwm crassifol wm. SENJAMIN CARRINGTON (1827-93) collected in various HISTORICAL 9) districts in Scotland. He forms a landmark between the time of Hooker and Greville and the present, and advanced our knowledge of Hepatice greatly. His British Hepatice, so far as completed, was published in 1874-76. He dis- covered Hremonotus myriocarpus during one of his visits, and also added Harpalejeunea ovata to the Scottish flora, probably also Gymnomitrium crenulatum and Marsupella Boeckit. Wititiam NIcHoL (1836-59). A few of Dr Nichol’s specimens appear to be incorporated in the Greville Her- barium, but otherwise no trace of them has been found. He was an acute botanist and may have been the first who found some of our species. JOHN SADLER (1837-82) added Riccia bifurca ? GEORGE Epwarp Hunt (1841 ?-73) discovered Mar- supella sphacelata on the Cairngorms, and probably also added Gymnomitriwm alpinum to our flora. JOHN WHITEHEAD (1833-96) was the discoverer of Mar- supella nevicensis. JOHN Sim (1829-1901) collected in the north-east counties and in Shetland. He added Gymnomitriwm adustum, Marsupella sparsifolia, Lophozia longidens, Cephalozia leucantha, Prionolobus Massalongi, Lepidozia trichoclados, and Frullania fragilifolia. ALEXANDER M‘KINLEY appears to have added Nardia minor and Plagiochila punctata. JOHN STIRLING STIRLING (d. 1900) investigated the flora of Stirlingshire with Mr R. Kidston. He appears to have done most of the part which related to Hepatice. Rey. JOHN FERGUSSON (1836-1907) collected in various parts of the Highlands. His additions to our flora are Fossombronia Wondraczekii, Marsupella ustulata, Hap- lozia atrovirens, Jamesoniella autumnalis, Harpanthus Flotowianus, Cephalozia pleniceps, and Scapania rosacea. CHARLES Scorr (1864-1907) collected in several parts of the south of Scotland and in Argyllshire. He added Mar- supella Pearsoni to our flora. For most of the dates of the above deceased botanists I am indebted to the indispensable Biographical Index of British and Irish Botanists, by Britten and Boulger. Mr Wiiu1Am Evans, Edinburgh, has investigated several 6 THE DISTRIBUTION OF HEPATICZ IN SCOTLAND of our south-east counties for hepatics, and has added Cephaloziella myriantha to the flora. Mr Perer Ewine, Uddingston, has collected in many districts and has materially increased our knowledge of the distribution of the species in Scotland. He has added Sphenolobus politus, Odontoschisma Macowni, and Sea- pania crassiretis. Rey. Davip LILure, Watten, has investigated the flora of the extreme north of Scotland, especially that of Caith- ness. He has made the additions:—Lophozia Kawrina, L. atlantica, and Anthoceros levis. Mr James M‘Anprew, Edinburgh, has done much ex- cellent work, especially in the south of Scotland. He published a List of the Hepatice of Kirkcudbrightshire in Trans. Dumf. Nat. Hist. Soc., 1887-90, also a list of the Hepatice gathered at Moffat in 1891. He has added to our flora Fossombronia Dumortiert, Sphenolobus Pear- soni, Radula voluta, and R. aquwilegia. Miss K. B. Macvicar, Edinburgh, has added Calypogeia sphagnicola, Mr James Micute, Balmoral, added Sphenolobus Hellerianus. Mr JAMES Murray, formerly of the Scottish Lake Survey, discovered Scapania nimbosa in Scotland. Mr GkrorGE STasier,! Levens, collected many species in the Balmoral district, and published a list of these in Trans. Bot. Soc. Ed., 1902. He added Lophozia guttulata to the flora. Mr WitiiaAmM West, Bradford, has collected in various districts of Scotland. He has added Gymnomitrium varians and Lophozia Wenzelit. Mr WititAM YounG, Kirkcaldy, has added several interesting species to the county lists from various parts. PROFESSOR WEISS, Manchester, has added Cololejewnea mucroscopica to our flora. The author has been working at the distribution of our Hepatice during the last twelve years and has made the additions to our flora:—Aneura incwrvata, Marswpella condensata, M. Sprucei, M. Jérgensenii, Nardia Breidleri, NV. subelliptica, Lophozia heterocolpa, L. obtusa, Sphenolobus 1 Died January 1910, GENERAL NOTES ON THE FLORA 7 quadrilobus, S. exsectus, Acrobolbus Wilsonii, Pedinophyl- lum wnterruptwm, Leptocyphus cuneifolius, Lophocolea spicata, Geocalyx graveolens, Prionolobus — striatulus, Cephaloziella Limprichtii, Adelanthus decipiens, Caly- pogera suecica, Radula Carringtonit, Cololejewnea Rosset- tiana, Leyeunea Macvicari, Drepanolejewnea hamatifolia. GENERAL NOTES ON THE FLORA As Hepatic usually form only a small part of the vege- tation of a country and are mostly confined to localities or habitats where there is a considerable amount of per- manent moisture, which must generally also be combined with shelter, their occurrence is local and is much less general than is the case with mosses. For ecological classi- fication they must be taken in conjunction with other Bryophytes to form subordinate communities or small patches of mixed vegetation. To this there is one excep- tion, where hepatics may be considered as dominant, namely about the summits of some of our highest mountains, of which Ben Lawers is the most distinctive. Here we have what Warming terms “ fell-field,” where the mean tempera- ture of the warmest month is low, rain and mist abound, the soil is cold and is never completely covered with vegetation. We find that near the summit of such a hill, hepaties, though occurring as scattered patches, form the dominant vegetation, and that we have thus an_hepatic-formation. The patches are low, flat, or cushion-like, the plants beng densely compact, the stems usually deeply buried in the soil, with only a small part above the surface; the leaves are nearly always imbricated and are mostly brown in colour. As most of the patches are formed by species belonging to the genus Marswpella and to the Marswpella- like section of Gymnomitrium, it may be named the Marsupella association. The species forming this associa- tion are Marsupella ustulata, M. condensata, Gymno- mitrium varians, G. crassifolium, G. adustum, G. con- cinnatum, G. corallioides, Nardia Breidleri, N. scalaris, Anthelia Juratzkana, A. julacea, Plewroclada albescens, 8 THE DISTRIBUTION OF HEPATICZ IN SCOTLAND Diplophyllum albicans, and D. taxifoliwm, most of which are usually present. With these are seen a few species of laxer habit, growing among such mosses as Dicranwm falcatum, notably Lophozia alpestris, L. ventricosa, and L. Floerkii, also occasionally a still larger species of xerophytic type in Plilidium ciliare. This formation extends further down the northern and eastern sides of a mountain than down the southern or western, and especially in depressions where snow remains throughout part of the summer. On the summits of many of our highest hills the soil occurs only in patches, and on these patches hepatics are either dominant or are sub- ordinate to mosses. A larger number of our hills, however, especially in the Gabbro and Torridon Sandstone districts, are practically without vegetation on their summits. Occasionally the summits and dry exposed ridges have a moss formation owing to the dominance of Rhacomitrium lanuginosum. In this case hepatics are almost absent. On many hills of rather less elevation, especially in schistose districts, the soil is completely covered with grasses on the summit, this being a “closed” formation instead of the only partially covered soil of the “ fell-field.” On several of the hills on the western watershed of the Highlands between 1700 ft. and 2000 ft. alt. or sometimes slightly higher, there is an interesting associa- tion of species, mostly of the Atlantic type. These are Mastigophora Woodsii, Jamesoniella Carrington, Scapania ornithopodioides and more rarely S. nimbosa, Anastrophyllum Donianum, Herberta adunca, Anastrepta orcadensis, Plewrozia purpurea, and Bazzania tricrenata. This may be named the Mastigophora association. It is found on shady, somewhat moist ground, usually either on rock ledges, or between boulders in rough ground among grasses and scattered plants of Calluna or Vaccinium. Frequent associates in the latter habitat are Leptocyphus Taylor: and Scapania gracilis. Some associations of hepatics are mentioned in the sketch of the Provinces, and a list of the Sphagnum-moor or peat- moss species is given in the section dealing with Habitats ; but little has been done in Scotland among Bryophytes froin an ecological point of view, and the investigation is GENERAL NOTES ON THE FLORA 9 of a different nature from that of a floristie work such as this. Comparatively few species in Scotland are confined to any particular habitat. This especially applies to the High- lands, where the humid conditions are so favourable for their existence, that we find them on different situations, such as on both rocks and trees, which in a less favourable country would be limited to one or the other of these positions. Ina large part of the south of Scotland, and towards the east coast, the climate is drier, and various species are more limited to special habitats, as appears also to be the case on the Continent. The presence or absence of continual moisture is the ruling factor. A few species grow almost equally well under either condition, but the very great majority do not. To a few species dry soil or dry rock is necessary, but the prevalence of hepatics in any part of our country depends on there being a considerable amount of moisture. When withdrawn to any great extent, hepatics disappear. This is well seen in a district favour- able for hepatics, as in the West Highlands, where species will be found in quantity in the natural woods, but when the woods are thinned the species decrease, their place being taken by mosses, in which group there are more xerophytes. Hepatics cannot withstand competition with mosses except in the most humid parts of woods. We see on tree stems and rocks on which the former have first taken hold, that a moss, as Hurhynchium myosuroides, perhaps follows, and the hepatics are choked. The effect of drainage is almost entirely to destroy the hepatic vegetation, except in the case of those which manage to find a suitable habitat at the moist side of the drain. They are scarce in the region of cultivation, this region being in large measure one of small rainfall and absence of shade, and likewise scarce in those districts of the subalpine region where the rock seldom appears on the surface, as over almost the whole of the upland parts of the Lowlands. They are generally plentiful over the whole of the uncultivated regions of the Highlands, where the rainfall is large, but are in small quantity usually on the south and west sides of hills, and plentiful on the north and east sides, this being a matter of moisture. Species are scarce on trees in the 10 THE DISTRIBUTION OF HEPATICA IN SCOTLAND drier and exposed districts, as transpiration is excessive, the only one which can be considered at all frequent in such a habitat being the xerophytie Frullania dilatata. The opposite condition is seen in the shady ravines of the West Highland coast-line, where the moist atmosphere and comparatively small amount of light hinder transpiration ; here we find hepatics in quantity on the stems of trees as well as on rocks, ete. In moist soils the most important division is into those which are peaty and those which are not. The geological formation of the rocks, except in the case of limestone, is almost a negligible factor, further than whether they form a soil retentive of moisture or not. The sandstone and voleanic rock districts, except granite, are nearly always poor in species, even in the most favour- able climatic districts, while in schistose rock districts there are usually species in plenty. A few species are more frequent when there is some lime in the soil, but no species is contined to this soil in Scotland, unless it be in the case of Metzgeria pubescens and Lophozia turbinata. Also a few species, as Nardia scalaris, are rare on limestone. Two rare species, Marsupella sparsifolia and Sphenolobus Pearsoni, have only been found with us on granite, and Chandonanthus setiformis is much more common when on this formation. As with habitats so it is with geological formations; in our moist insular climate, so favourable for the growth of hepaties, species do not limit themselves to a particular kind of rock as they appear frequently to do in countries less favourable for these plants. RAINFALL As the distribution of hepatics is largely a question of climate, the amount of rainfall has an important bearing on the subject. We find in Scotland that hepatics are scarce in all districts which have less than an average of 30 in. of rain annually. These districts form a narrow border along the east coast from Caithness to Berwick. Here also there is in general little shelter, but strong dry RAINFALL 11 winds favouring transpiration are frequent. We find, how- ever, that even where these latter unfavourable conditions are absent in the district of small rainfall, as in sheltered ravines or dens, hepatics are still scarce. It must be added that the rock formation in which these dens occur is in general less retentive of moisture than in the dens in the wetter district of the west coast, and therefore less suitable for hepatics, and probably also with less humidity; but even with similar rock character in the two sides of the country the scarcity of hepatics in the dens of the drier districts is striking. The deficiency in the number of species in the drier districts is not so noticeable as the general scarcity of hepatics. Prolonged search over a considerable tract of a dry district will result in the discovery of nearly as many species as in a wet district, leaving out of account the peculiar Atlantic species of the western side of the country, but there can be no comparison between the amount of hepatic vegetation present in each. A larger number of plants will probably be seen in a single day’s ramble in a wet district than would be found during a year’s searching over a much larger area of a dry district. Lists of species made under different amounts of our average rainfall have not resulted in much matter of interest, but some general features may be given. There are about 145 species which have been found on the low ground, and of these, 93 have also been found, among other places, in the district under 30 in. Of the 145 species there should be excluded 23 Atlantic species of the west coast, and of the 93 there should be excluded 11 peat-moss species, as the latter being on permanently wet ground have a wide distribution independently of the annual rain- fall; Also from the 145 species may be excluded four which have only been found in shady ravines, when in the drier districts, as the humidity must be considerably above the average. There are thus 82 species out of 118 which have been found in the drier districts, and a few of these are local and rare, but this applies to both factors. Taking into consideration the comparatively small area which there is under the 30 in., we see that the actual number of species in Scotland is not much affected by the rainfall. 12 THE DISTRIBUTION OF HEPATIC IN SCOTLAND It would be a very different matter if a census of the number of individual plants within equal areas of the dry and wet districts were taken. The apparent absence of Atlantic species of Lejewnew, and some other species of the same type, from the low ground of South-West Scotland is most probably due to the small annual rainfall, as some of them occur in the neighbouring wetter districts at the foot of the hills, although further from the sea, the geological formation being the same. Few of the Atlantic species are found below 30 in. They are most common in that part of the coast which has between 50 and 70 in. None of the following Lejeunee have been found under the 40-in. rainfall, viz. calyptrifolia, microscopica, Macvicari, hamatifolia, and ovata. To these should be added L. minutissima, but this species has only been found in two localities in Scotland and cannot be taken into account in this regard. It is not a purely Atlantic species, and it occurs in England, where it is less rare, in some localities under the 40 in. Subalpine species are uncommon below 40 in. except in the proximity of mountains and in the extreme north, especially Shetland, where latitude has some effect. The peat-moss species, as already stated, have a wide range in rainfall. The subalpine species Preissia quadrata, Lophozia Muelleri, and Scapania subalpina have been found on moist ground in sand-dunes below the 30-in. rainfall. LATITUDE LATITUDE in Scotland hardly affects the actual presence of any of our low-ground species of hepatics except in the case of the thalloid genera of Southern type, Riccia, Targionia and the introduced Lunuluria and perhaps a very few foliose species also of the same type, as Bazzunia trilobata, Madotheca levigata, and Cephalozia Francisci. The absence in the extreme north of some of our other low- ground foliose species is in all probability due to the absence of shelter, as they are all plants of moist sheltered LATITUDE ia ground, especially in wooded ravines. With regard to the alpine species, the ecological conditions in the north of Scotland are unfavourable for their presence. There are, however, two or perhaps three species which occur in the Highlands on hills of a similar height to those in the Low- lands, and the apparent absence of which from the latter is probably due to latitude. The ecological conditions are likewise unfavourable in the extreme northern islands of Orkney and Shetland, so much so that no alpine species have been found on the former and few in the latter. Those which are found in Shetland descend to a lower level than on the mainland, but the lower limit of altitude does not appear to be appreciably affected by latitude on the mainland except to a very limited extent. The main factor which affects the lower limits on the mainland is that the ecological conditions on the West Highland coast are favour- able for such downward extension, as is also the case with other countries of similar features, and this also applies to other forms of vegetation. Our climate being insular, there is little difference between the extremes of temperature due to latitude, but there is a considerable difference on account of longitude. Along the whole length of the western seaboard there is hardly any appreciable difference of winter temperature, and this temperature considerably exceeds the winter temperature of the centre and east of the whole of Scotland, and, it may be added, of the similar districts in England. On the other hand, the summer temperature is higher, and there is a greater amount of sunshine, in the centre and east of Scotland in corresponding latitudes than there is on the west, and the amount decreases with latitude. We should thus expect to find that Southern species, which require greater summer heat, would reach a higher latitude on the east and in the centre of the country than on the west, and this is mostly the case; also that the Southern species which are affected by latitude in our country mostly belong to the thalloid group, which are dependent on a con- siderable amount of summer heat in the soil. 14 THE DISTRIBUTION OF HEPATIC IN SCOTLAND ATLANTIC SPECIES THE Atlantic species of hepatics are those which are confined, or almost so, to the west coast of Europe, includ- ing a short distance inland and the Atlantic islands, a few extending along the Mediterranean, and still fewer being also found in subtropical and tropical America, the West Indies, and other parts of the world. These species are more plentiful in the British Isles than in other parts of Europe, some being only known from our island. The first fact to be noted is that the prevalence of the Atlantic species in Scotland is, in general, proportionate to their proximity to the west coast; the further one goes eastward, the rarer they become. The actual proximity of the sea on the east coast does not favour their occurrence except in a very few cases to be afterwards mentioned. The distribution of Hepaticw is mainly dependent on climate, the chief requisite being moisture. In the case of nearly all Atlantic species an absence of a low extreme of temperature is also necessary. This combination does not extend far from the west coast, and the distance to which it extends marks the point to which these species are prevalent. Next to moisture in the atmosphere the most important requisite is the physical condition of the soil. Where the nature of the rocks is such that their disintegra- tion does not form a moist and retentive soil, it will be found that even under the otherwise most favourable conditions on the west coast Atlantic species are scarce or absent. This is very noticeable in ravines running through sandstone and some volcanic rocks. Nearly all species of hepatics are scarcer in such ravines, but the Atlantic species being the most delicate, are affected in a more marked manner. The next point in treating of the distribution of these species is that too much importance must not be given to the watershed dividing Scotland west and east. Water- sheds in themselves have no relation to the distribution of Heputicw, whatever they may have in the case of phanerogams. ‘The north and east sides of the watershed, with their constantly moist ground, have hepatics in plenty, ATLANTIC SPECIES 1 while the dry sun-exposed south and west sides have few. An instructive instance can be seen where our main watershed divides Argyllshire to the west and Perthshire to the east, at the part of the latter county where its eastern watershed lies nearest to the west coast. This is at Tyndrum and Ben Laoigh. The west or Argyllshire side is dry and sun-exposed, with little suitable ground for hepatics, while the east and north sides, both belonging to the watershed of the German Ocean, have abundance of hepatics, among which are the characteristic Atlantic species Leptocyphus cuneifolius, Mastigophora Woodsii, Scapania nimbosa,and Cololejeunea microscopica, which have not been found elsewhere on our eastern watershed, with the excep- tion of the Scapania, which has been found on one locality in Kast Inverness close to its western boundary. It is the proximity of the Atlantic, not the watershed, which is of consequence, provided that there is moisture and shelter for these species. It is only in places with such moisture and shelter that the low-ground species of the Atlantic type extend eastward from the west coast. ‘These condi- tions prevail a short distance over the western watershed in the Trossachs, and this is the most eastern point in the centre of Scotland where the hepatic flora is rather western than eastern. Owing to the configuration of Scotland, especially with its south coast being practically on the Atlantic, longitudinal lines for the whole of the country cannot be satisfactorily quoted. Those species of Atlantic hepatics which are confined to the mountains have in several cases a more extended distribution eastward. This is so principally with those which occur on moist rock ledges, some of which are found in the Aberdeenshire Grampians. The wet climate of the mountains approximates more to that of the west coast, and these species are able to withstand a considerable amount of cold. On the other hand, our only alpine Atlantic species confined to dry rocks, Gymnomitriwm crenulatwm, while it is a common plant on the west coast, becomes gradually rarer as it extends to the east, until it becomes exceedingly rare on the Aberdeen Grampians. There is very little sheltered ground on our north coast. None of the characteristic species of the west coast have been found 16 THE DISTRIBUTION OF HEPATIC IN SCOTLAND there, but one Atlantic species, Plewrozia purpurea, which atfects wet exposed moors, is found in quantity in the northern parts of the mainland. The Atlantic species are in general scarce on the exposed Orkney and Shetland groups of islands, but they are more in evidence there than on the northern mainland. Our Atlantic species may be divided as follows, as far as our knowledge of their distribution allows in the meantime. 1. Species known only on the western watershed : Sphenolobus Pearsoni. Colurolejeunea calyptrifolia. Acrobolbus Wilsonii. Cololejeunea minutissima. Plagiochila tridenticulata. Lejeunea Macvicari. Adelanthus decipiens. Drepanolejeuneahamatifoha. Lepidozia pinnata. Harpalejeunea ovata. Radula voluta. Marchesinia Mackaii. R. aquilegia. Jubula Hutchinsiee. R. Carringtonii. Frullania microphylla. Sphenolobus Pearsoni extends inland to the Kells range of hills in Kirkeudbrightshire. This minute subalpine and alpine species, which is apparently confined to granite, will perhaps be found on the Eastern Grampians. Radula aquilegia extends inland to New Galloway. Harpalejewnea ovata is more frequent inland and extends rather further than the others of its group. 2. Species also on the east coast near the sea-shore, but not inland : Lophocolea spicata. Frullania germana. The first of these is almost contined on the west coast to rocks on the shore. The only known locality for it on the eastern side is in a ravine close to the shore in Berwick- shire. The second is frequent on rocks on the shore of the west coast. Its eastern locality is on the Isle of May. 3. Species extending for a short distance over the western watershed into the eastern : Plagiochila punctata. Scapania nimbosa. Leptocyphus cuneifolius. Cololejeunea microscopica. Mastigophora Woodsii. ATLANTIC SPECIES 17 Plagiochila punctata extends further inland than the others, reaching to Killin. I should have felt inclined to include Microlejeunea wlicina here. It is a western species in Scotland, extending inland to the Trossachs, but it has been found in several places in the centre of Europe. It prefers a drier and less sheltered situation than the un- doubted Atlantic species of its family, and is probably of a more robust constitution. 4, Species common on the west coast, continuing frequent in some parts of Central Scotland, but becoming very rare toward the east coast : Metzgeria hamata. Plagiochila spinulosa. Gymnomitrium crenulatum. Saccogyna viticulosa. Lepidozia Pearsoni. Pleurozia purpurea. Scapania gracilis. 5. Subalpine and alpine species common to the western watershed and the Eastern Grampians: Gymnomitrium crenulatum. Herberta adunca. Marsupella Boeckii. Scapania gracilis. Jamesoniella Carringtoni. S. ornithopodioides. Anastrophyllum Donianum. Anastrophyllum appears to have its headquarters in the Eastern Grampians, unless further search shows this to be in Sutherland. Herberta seems to be confined in the Eastern Grampians to the Forfarshire hills. The Marswpella is a minute species with its distribution very imperfectly known. The others are much more plentiful on the western watershed. One recent addition to our flora, Lophozia atlantica, has been found only in a few localities. It cannot be classed at present in any of the above divisions. Comparing the Atlantic species in Scotland with those in England and Ireland as regards their distribution, we find : 1. Species which occur in Scotland but have not been found in England and Wales: Jamesoniella Carringtoni. Mastigophora Woodsii. Anastrophyllum Donianum. Radula Carringtonii. Acrobolbus Wilsonii. Pleurozia purpurea. Leptocyphus cuneifolius. Lejeunea Maevicar. TRANS. BOT. SOC. EDIN. VOL. XXV. 2 18 THE DISTRIBUTION OF HEPATIC IN SCOTLAND 2. Species which occur in Scotland but have not been found in Ireland: Marsupella Boeckii. Lophozia atlantica. Jamesoniella Carringtoni. Sphenolobus Pearson. Anastrophyllum Donianum. Lejeunea Macvicari. 3. Species found in England, but not in Scotland: Dumortiera irrigua. 4, Species found in Ireland, but not in Scotland: Dumortiera irrigua. Bazzania Pearsoni. Plagiochila ambagiosa. Radula Holtii. P. Owenii. Lejeunea flava. P. killarniensis. L. Holtii. Cephalozia hibernica. Microlejeunea diversiloba. Adelanthus dugortiensis. Probably all the European Atlantic species, with the ex- ception of Scapania Jérgenseni from Norway, have been found in the British Isles, and the following have not been found elsewhere in Europe: Acrobolbus Wilsonil. Radula Holtii. Plagiochila ambagiosa. Lejeunea flava. Cephalozia hibernica. L. Holtii. Bazzania Pearsoni. L. Maevicari. Scapania nimbosa. Microlejeunea diversiloba. Radula voluta. Frullania microphylla. To these might be added Metzgeria hamata, Jamesoniella Carringtoni, Mastigophora Woodsii, Cololejeunea micro- scopica, and Frullania germana, which have been found elsewhere only in the Faroe Islands. The flora of these islands is generally admitted to be British rather than Continental. It will be noticed that seven of the species peculiar to the British Isles have been found only in Ireland. The species common to the west of Norway and west of France are: Plagiochila punctata. Saccogyna viticulosa. P. spinulosa. Adelanthus decipiens. Lepidozia pinnata. Harpalejeunea ovata. Scapania gracilis. ATLANTIC SPECIES 19 Norway has the following which have not been found in France : Gymnomitrium crenulatum. Leptocyphus cuneifolius. Marsupella Boeckii. Herberta adunca. Anastrophyllum Donianum. Scapania ornithopodioides. Sphenolobus Pearson. Radula aquilegia. Plagiochila tridenticulata (as R. Carringtonii. P. exigua). Pleurozia purpurea. The following have been found in France but not in Norway : e Dumortiera irrigua. Drepanolejeunea — hamati-' Lophocolea spicata. folia. Colurolejeunea calyptrifolia. Marchesinia Mackaii. Cololejeunea minutissima. Jubula Hutchinsie. The Atlantic species are the most interesting of our Hepatice. They differ from our other groups, Northern, Continental, and Mediterranean, in that their origin in our country cannot be traced to any known geological period. The peculiar British species, and some of the others, are sub- tropical or tropical. They are the relics of an early warmer period. Comparatively few have been found in fruit, and as gemme are also unknown in some of them, they are in many cases no doubt in process of extinction. Further investigation will doubtless alter our views on some of these species, and it is with some hesitation that I have included the generally accepted Atlantic species Gymno- mitrium crenulatum and Herberta adunca, as they have been recorded from Alaska. Perhaps all alpine Atlantic species may be found to be in a different category from the species peculiar to sheltered places on the low ground, but here as with other groups there are always a few species which are difficult to classify. WESTERN SPECIES OTHER THAN ATLANTIC Most of the low-ground species are found in greater abund- ance on the west side of the country than on the east, but the following show a distinct preference for the west side: 290 THE DISTRIBUTION OF HEPATICZ IN SCOTLAND Marsupella Funckii. Trichocolea tomentella. Sphenolobus exsectus. Madotheea leevigata. Harpanthus scutatus. Lepidozia trichoclados. Bazzania trilobata. Also the following, which are sometimes considered to be Atlantic species: Anastrepta orcadensis. Calypogeia arguta. Sphenolobus ovatus. Microlejeunea ulicina. With these must be included two alpine species, Gymno- mitriwm obtusum and G. alpinwin. The above species are either Western Continental, ze. most prevalent in the western part of Europe, or are species which at least prefer the moister regions of Europe. Sphenolobus exsectus is a recent segregate with an imper- fectly known distribution; it may perhaps have to be excepted. EASTERN SPECIES THE following species show a preference for the eastern side of the country, especially to the north of the Forth. A few are confined to that side, but are rare, having been found only in a few localities, and have been mostly added to our flora in recent years: Riccia crystallina. Sphenolobus Hellerianus, R. fluitans. Lophocolea bidentata. Lunularia cruciata. L. cuspidata ? Targionia hypophylla ? L. heterophylla. Haplozia cordifolia. Cephalozia Francisci, Lophozia turbinata. Ptilidium ciliare. L. badensis. P. pulcherrimum. L. guttulata. Diplophyllum obtusifolium. L. longidens. Scapania paludosa. L. cylindracea. Radula Lindbergii var, ger- L. Floerkii. mana. L. Baueriana. Madotheca platyphylla, L. gracilis. M. rivularis. These are mostly of the Continental, as distinct from the Western Continental, type. The more common occurrence HABITATS sh of Lophozia turbinata and L. badensis is doubtless due to the greater area of soil containing lime on the eastern side of the country.