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 A HISTORY OF CORNWALL Britain a brand new species, should suffice to arouse the interest of a few resident botanists. From the eastern boundary of the county to Falmouth there are only five records for so common a species as Chara fragilis, and from Bridgerule to Hayle, a good two-thirds of the county, G. vu/garis, with three of its varieties, has only eight recorded stations. The appended table shows that not a single Chara has been reported from the Fowey division, and that only one species is known to occur in the Lower Tamar area. No one can accept this as a correct index of the Chara flora of those parts. As a British plant C. fragifera y Durieu, is quite unknown outside the Lizard and Land's End divisions. Around Helston, on the Lizard Downs, near Marazion, on Chy-an-hal and Hale Ager Moors, west of Penzance, and on Tresco, one of the Scilly Islands, it can always be re- lied on if the summer is not an abnormally dry one. C. polyacantha^ Braun, and C. baltica var. affinis, H. & J. Groves, are confined to a restricted area west of the Lizard Head. C. hlspida, Linn., although generally distributed in other parts of the country, has only been found at Swanpool near Falmouth and at Kynance near the Lizard. Nitella hyalina, Agardh, as already stated, is one of the rarest of British plants, a few square yards in the Loe Pool representing the area of its known occurrence in the British Isles. N. graci/is, Agardh, was reported for the Goonhilly Down in the PJbytofogfst, 1845, but in the absence of voucher specimens and recent confirmation the statement must be accepted with caution. Those were days when the Gharacece of this country were but little understood, and it is almost certain some other species, probably N. opaca, was mistaken for N. graci/is. Chara fragilit, Desv. i, 4, 6-8 var. barbate, Gant. 8 var. capillacea, Coss. & G. 8 fragifera, Durieu. 7, 8 - aspera, Willd. 6, 7 var. destnacantba, H. & J. G. polyacantha, Braun. 7 - baltica var. affin'u, H. & J. G. bispida, Linn. 6, 7 fu/garit, Linn, i, 5, 7, 8 Chara vulgaris, Linn. var. kn&bracteata, Kuetz. 5, var. atrovireni (Lowe). 8 var. melanopyrena, H. & J. G. canescens, Loisel. 6, 7 Nitella grac'iRi, Agardh. 7 ( ?) translucent, Agardh. 46, 8 fiexllii, Agardh. i, 4-8 opaca, Agardh. I, 2, 6, 7 byalina, Agardh. 7 MOSSES (Musci) Cornwall is exceptionally favoured by its physical conditions for the growth of mosses. The moist air, warmed by the Gulf Stream, conduces to the growth of many southern species that find here con- ditions similar to those which obtain in the south-west of Ireland ; and a few south European species have in Cornwall their northern limit. On the highlands of the Bodmin Moors a number of subalpine species grow, and on the calcareous sand of Hayle and St. Minver, and the serpentine formation of the Lizard, others grow which are absent from 74