ROSA ARVENSIS 3 
R. dibracteata Bast. in Britain, but this point will be dealt with 
in its proper place 
Key To Bririsa SPECIES. 
Stems more or less og clothed with small acicles as well as 
1 larger scattered prickle R. gallicoides aT 
Prickles scattered, carson or nearly so 
omen tall, stout and stiff; leaflets large, eS 
2 dibracteata Bast. 
Stems short, weak or trailing; leaflets medium or small, acute or 
b 3 
3 {Pe seston smooth R. erronea aie 
Peduncles finely — 
bores fully biserrat: r. biserrata Cnt 
Leaflets uniserrate or oly very finely and setae ‘piserrate ...... 
5! Petioles considerably glandular ar. scabra a 
| Petioles eglandular or very ae so 6 
Leaflets elliptical; fruit ellipsoid ..........::s.eeseeeeeeeeee R. ovata Lej. 
6+ Leaflets oval or broadly so ; Pfruit suborbicular or ovoid 
R. arvensis Huds. 
Rosa ARVENSIS 
Hudson, Fl. Angl. p. 192 (1762). 
“Globose fruit and aig 9 glabrous. Stem and petioles 
prickly. Flowers subcymo 
There has been a Soa dcasein on the part of some Continental 
botanists to restrict Hudson’s name to the rare form o h 
hairs were pieces tags unless they were siete in *oeblarebie 
uantity or were very conspicuous. Moreov ver, the smooth 
peduncled form is extremely rare in Britain, and is not likely to 
have been selected as the subject of Hudson's description. Still 
it must be = a that it is exceedingly vague, and will readily 
cover several species of the section Canine. 
Those bot reset te hold the above view = our common 
British form as R. repens Scopoli, Fl. Carn. 355 (1772), 
alternate, subpinnate. Fruit subro Lea jugate, the 
impair equal. Peduncles 1-3-flowered, pe hairs red, capitate. 
Petals white. Fruit glabrous.” The + Hudson’s species 
modern one is to regard it as the type, with glandular peduncles, 
Scopoli’s species being merely a weak form 
R. arvensis is recognizable by its trailing habit, its long flaccid 
trable 
stems being densely interwoven into an impene thicket. 
They are usually glaucous and very liek purple, the prickles 
being few but stout and h on the main stem, much smaller 
and finer on the branches. The leaflets are usually oval and sub- 
obtuse, but, as in all roses — range of variation in shape and 
colour may be found. Pherae always coarsely simply serrate. 
b2 
