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 A HISTORY OF SURREY and Mr. Ferguson Shepherd of Staines have been instrumental in adding largely to the county records. The present writer has also worked for many years at the distribution of species through the eight watershed districts. The species recorded include several mosses of great interest, chief among them being Buxbaumia aphylla, which formally grew upon mud banks at Virginia Water on the border of the county, the almost equally rare Pbyscomitrium sphcericum, which is abundant on the muddy margin of a pond near Felbridge, and Weisia rostellata, from the mud of a drained pond at Dormansland. Campylopus subulatus is another rare species of recent discovery, of which a single tuft was gathered by the writer in 1899 at Addington on dry stony ground. Several commoner species are of interest from their occurrence under unusual conditions. Pleurochcete squarrosa, which is most frequently found by the sea, is well established on the steep northern slopes of Box Hill, and Brachythecium megapolitanum, another maritime plant, grows close by ; two other mosses which frequent sub-alpine regions, Bartramia ithyphylla and Rbacomitrium canescens, occur, the former on a soft sandy bank near Dorking and the latter on moory commons and by the side of stony roads. Hypnum imponens and H. giganteum are rare species which appear to be becoming better known as new records are multiplying. The former has no doubt been confounded with H. cupressiforme var. ericetorum, which it much resembles ; it grows on most of the larger commons, often in profusion. The Sphagna are well represented. S. medium recently made known to us as a British species is abundant on Pirbright Common ; 5. molle from the same locality is perhaps our rarest bog moss, although S.fimbriatum has so far been recorded from only one locality. S. Girgensohnii has not yet been reported, but it is not unlikely to occur in one of the more elevated bogs. Instead of a single list enumerating all the species found in the county, the most interesting or characteristic mosses recorded in each watershed division are given, with, in the case of rarities, a reference to the localities. 1 . BLACKWATER. The smallest division, forming the extreme north- west of the county. The greater part is composed of Bagshot Sand with a small area of chalk at the base. The hills forming the eastern boundary are covered with heather and pine woods, and with a few bogs at the base. Aulacomnion androgynum, Schwgr. ; Bartramia pomiformis, Hedw. ; Philonotis fontana, Brid. ; Brachythecium albicans, B. & S. ; Hypnum cordifolium, Hedw. 2. UPPER WEY. The southern slopes of the chalk downs form the north border of this district, and a broken ridge of high hills of Lower Greensand forming the highest land in the county lies about halfway between them and the Sussex border. To the south of this ridge extends the Weald Clay characterized by oak woods and plantations. In the west are large commons with numerous ponds, bogs and alder swamps. 52