176 Proceedings of the Royal Society of Edinburgh. [Sess. 



island owes a good deal of its plant-covering to lichens, of which the following 

 species are the most conspicuous : — Kamalina polymorpha, both large and 

 small forms, R. scopulorum, and Alectoria jubata are all abundant, especially 

 on cliffs and the vertical sides of rocks, from which they hang in profusion. 

 Parmelia saxatilis, Cetraria aculeata, and Sphaerophoron coralloides cover 

 rocks that are beyond the influence of the sea spray, Amphiloma lanugin- 

 osum is abundant in shady corners about the rocks and cliffs, and Peltigera 

 polydactyla occurs amongst rough grass, but is not abundant. 



As would be inferred from the nature of the environment, Hepaticse are 

 scarce. Lophocolea bidentata occurs about pools and other damp places, 

 and in the cave. Jungermannia ventricosa grows in damj) places below 

 rocks, but is not abundant ; Nardia scalaris, growing with Cephalozia Starkii, 

 also Lunularia vulgaris and Conocephalus conicus, carpet the sides of the 

 cave. Mosses are of much more frequent occurrence. Grimmia maritima 

 and Webera nutans are common on rocks ; a form of the latter species Avas 

 also fairly abundant. Respecting it, Mr H. N. Dixon, to whom a specimen 

 was submitted, writes as follows : — " It is a form or variety which I have 

 gathered once or twice, usually in mountainous country, and it comes near 

 the mountain form which I have referred to in the Handbook [of British 

 Mosses], 2nd edition, as like W. commutata." Polytrichum Juniperinum 

 occurs in scattered patches all over the island. Mnium hornum, Ambly- 

 stegium serpens, and Eurhynchium prselongum are all common in damp 

 places throughout the island.* 



The only ferns observed were Asplenium marinum, which grows 

 spai'ingly about the cliffs and in the cave, and A. Ruta-muraria, which is 

 very scarce. Excluding weeds in the cultivated spots and on ground 

 adjacent to them, the most abundant Phanerogams are as follows: — 

 Ranunculus repens, very common ; R. aquatilis, rather dwarf specimens in 

 some of the pools ; Cochlearia officinalis, very abundant in places ; several 

 variations occur in accordance with the environment, and in the cave there 

 is a very slender and somewhat pellucid form ; Cerastium tetrandrum, 

 scarce; C. triviale, very abundant; Stellaria media, common near the 

 houses, on rubbish-heaps, etc. ; Silene maritima, very abundant, and in the 

 cave there is a very long-leaved form ; Sagina apetala, common ; Potentilla 

 anserina and P. tormentilla, both abundant ; Sedum anglicum, very 

 abundant about the rocks (fig. 124) ; Callitriche verna and C. stagnalis, both 



* Since the above was written, Mr William Evans has pubhshed his observations on 

 the Bryophytes of the Isle of May, the specimens having been collected there at various 

 times from 1885 to 1908. He mentions 18 species of mosses and 7 hepatics, most of which 

 are very scarce. — Trans, and Proc. Bot. Soc. Edin., 1908, vol. xxiii., part iv., pp. 348-351. 



