vzr.flaccidifolius, and it there extends into Bedfordshire. Of the sub-erect forms, which are more frequent in the north of Britain or in peaty places, the same district gives R. fissus in considerable quantity, and Mr. Ben- bow has found R. Rogersii near Alderbourne. R. plicatus is not uncommon about Brickhill, while R. nitidus is so far restricted to Shalbourn Wood in the Ouse district, and there not quite typical. A very local species, R. latifolius, also grows near Brickhill, and with the last named belongs to the Sub-Rhamnifolian group. Of the Rhamnifolian brambles R. incurvatus grows near Fulmer, and R. rhamnifolius is widely distributed. R. Lindleianus is also common at Brickhill, and is frequent on the dry, heathy commons in the Thames and Colne districts. R. dumnoniensis is so far only known from north Bucks in the Ouzel district, as at Ivinghoe and Brickhill ; R. pulcherrimus is found at Brickhill, and is common in many parts of the heaths and woods of the Thames and Colne districts. The group Villcaules is represented by R. Selmeri, which occurs at Brickhill, and is a striking feature of Stoke and Fulmer Commons, and it just comes in the Thame district at Chequers. R. calvatus I have only obtained from Naphill Common in the Thames district. R. gratus, a local and handsome species, occurs at Heath in the Ouzel and Alderbourne in the Colne district. R. rhombifolius is very local, and is found at Wing in the Ouzel and Stoke in the Thames districts. The group Discolores, to which our commonest species R. ulmifolius or rusticanus belongs, has R. thyrsoideus in the Ouzel and Thames, and R. argentatus from Medmenham in the Thames district, and R. pubescens as the typical plant from Westbury Wild in the Ouse district, where brambles are very poorly represented. The Silcatici are represented by R. sivaticus from near Wycombe, R. macrophyllus which is widely distributed and rather common about Iver, R. Schlechtendalii from near Amersham, R. Salteri from Heath in the Ouzel district. Of the Vestiti group we have R. Sprengelii at Burnham in the Thames district, JR. pyramidalis from Brickhill and from the Thames and Colne districts. R. leucostachys is one of the species which is generally distributed, even in the woods and hedges of the Ouse district. R. gymnostachys grows at Brickhill. Of the Egregii we possess R. cinerosus from the Wycombe neighbourhood, R. mucronatus from Iver Heath, R. infestus from Brick- hill, R. uncinatus as a form collected by Mr. Britton at Mop End near Amersham, elsewhere only known from Gloucester and Monmouth, and R. Leyanus found by the Rev. E. F. Linton at Brickhill. Of the group Radulœ, R. radula is a rather common and widely distributed plant, occurring in all the districts, but chiefly as the var. echinatoides. The var. anglicanus occurs at Westbury in the Ouse and in several places in the Thames and Colne districts. R. echinatus is also rather common, and is one of the few species not uncommon in the woodland portions of the Ouse district. R. rudis is much more local, but I have found it at Moulsoe in the Ouse, Brickhill in the Ouzel, and Bulstrode in the Thames districts. R. oigoclados var. Neivbouldit, an endemic form, is apparently limited to Halton in the Thame district. Of the Sub-Kœhleria group
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