A HISTORY OF BUCKINGHAMSHIRE 



vzr.jiaccidifolius, 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. jissus 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. incur- 

 vatus 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. dumno- 

 niensis 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 Villkaules is represented by R. Se/meri, 

 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. cafoatus 1 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 Disco/ores, 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. pubescent 

 as the typical plant from Westbury Wild in the Ouse district, where 

 brambles are very poorly represented. The Sifoatici are represented by 

 R. sihaticus 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 

 Radultz, 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-Kcehleria group 



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