Page:VCH Cornwall 1.djvu/151

 BOTANY of West Cornwall was published in vol. i. new ser. of the same work (pp. 215, 422) by Dr. Ralfs. In 1884 (loc. cit. ii. 73, 379) Mr. R. V. Tellam published a very full list of the lichens of the eastern part of the county. T'be List of Scale Mosses and Lichens of Devon and Corn- wall, published at Plymouth in 1872 by Mr. E. M. Holmes, also con- tains a number of Cornish localities for lichens. Other lichenologists who have explored various parts of the county are the late Mr. Dawson Turner, Dr. H. B. Holl, Mr. E. G. Varenne, Mr. E. D. Marquand, the Rev. J. M. Crombie, and others. The largest contributors to the Cornish lists have undoubtedly been the Rev. T. Salwey, Dr. Ralfs, Mr. W. Curnow, and Mr. R. V. Tellam. Mr. Holmes has visited in search of lichens the boundary line of the Tamar from Mount Edgcumbe to Saltash, Whitsand Bay, Fowey, Padstow, St. Ives, Newquay, Bedruthan, Falmouth, Lizard, Penzance and Land's End. Lichens from these local- ities that do not appear in the published lists are mostly records taken from specimens in his herbarium. The characteristic lichens of the county are chiefly those that occur on maritime rocks, especially on granite, clay, slate, and serpentine. Those characteristic of hard limestone, and of mountainous or subalpine regions, are fewer in comparison, although there are many cretaceous species found on the shelly sand dunes, as at St. Minver, and on the mortar of old walls. The abundant oak coppices, clothing the sides of damp ravines, as in the neighbourhood of Bodmin, furnish many southern species ; others are found in the warm climate of Scilly Isles, Penzance, and the Lizard that are not found further north, or very sparingly so on the north-west of Great Britain, where the influence of the Gulf Stream is felt. Thus Lecidea Muddii is found on the coast in Westmorland, and Sticta Tbouarsii and S. crocata occur near Oban and elsewhere on the west of Scotland. Several species usually sterile in Britain have been found in fructification in moderate abundance in Cornwall. Amongst these may be especially noticed Roccella fuciformis and R. pbycopsis, Parmelia Borreri, P. caperata, P. perlata, and Pbyscia flavicans. The following are some of the rarer lichens found in the county, which are characteristic of a southern flora : Myriangium Duricei, found only in Cornwall and the Channel Islands, chiefly on ash trees ; Sticta aurata, found in the Scilly Islands, but extremely rare in Dorset and Hants ; S. Dufourei, Physcia speciosa, P. leucomela ; Opegrapba ampbotera elsewhere recorded only from Bala Lake in Wales ; Lecanora subexigua, L. discoretta, L. Ralfsii, Lecidea strepsodina, L. herbarum, L. scopulicola, Opegrapba lentiginosa, O. Ceesariensis^ O. grumulosa, Litbograpba petrtea, L. dendrograpba, Arthonia ilicina, Graphis Lyellii, G. Ruiziana, Stigma- tidium circumscriptum, Cbiodecton Sarniense, and the maritime species of Verrucaria. The Grapbidiei are particularly well represented in the county, almost as richly indeed as in the south-west of Ireland. Ramalina Curnowti, named after Mr. William Curnow, one of the princes of Cornish botanists, does not appear to have been detected elsewhere, 99