RUMEX KtrPESTRIS. d 



bearing a fully developed tubercle, which is very large and prominent, 

 covering nearly the whole width of the petal, oblong-ovoid, at least 

 ^ inch long by i^ broad, opaque almost pearly white when growing, 

 sometimes suffused with purplish-red on exposure (golden-orange 

 and finely shagreened on the surface when dry). Nut bright pale 

 brown, shining, faces broadly oval or ovate, pointed, about ie inch 

 wide. 



Whether these characters are sufficient to constitute R. rupestris 

 a distinct species is of course a matter of opinion. They approximate 

 it closely to R. conglomeratus, of which it may be a variety, but 

 from which it can be distinguished without difficulty by its com- 

 pact, upright habit with a tapering panicle confined to the upper part 

 of the stem, its narrower and more oblong root-leaves, its few and 

 narrow whorl-leaves, and its very much larger and blunter fruit-petals 

 and larger nut. 



It is the constant combination of these distinctions that must be 

 looked at. Singly the most important seem to be the large size and 

 form of the ripe-petals, tubercles, and fruit, and the characteristic 

 habit ; the latter has been very fairly likened by Grenier and 

 Godron to that of the N. American R. saUcifoUiis, Weinm. At the same 

 time it must be allowed that R. conglomeratus is a plant of a wide 

 variability, and is frequently met with under forms which depart 

 from the characters given in books. The type of this species may be 

 considered to be a straggling plant with divaricate branches, broad- 

 based stem-leaves which accompany every whorl except the very ter- 

 minal ones, and small fruit ; but there occur states which modify all 

 these points. A plant with ascending branches, narrower stem-leaves, 

 and most of the whorls leafless is not unfrequently named R. viridis 

 or R. nemorosus, and is in my opinion the plant gathered in Sussex 

 and considered " trigranulate nemorosus " by Dr. Boswell in the last 

 " Exchange Club Report," and perhaps also that figured in " English 

 Botany," on which see a note in the last volume (1875, p. 337). 

 R. nemorosus (R. sanguineus, (3. viridis ; R. Nemolapatlmm) seems to me 

 quite removed from R. rupestris, and very little prone to variation ; it 

 can be usually recognised by its tall, slender, lax habit, few but large 

 an -I somewhat flaccid stem-leaves, quite leafless whorls (except the 

 basal one or two), and single tubercle, which is globular. Stress 

 has been laid by some botanists on the position of the joint 

 in the pedicel as a distinctive mark between R. conglomeratus 

 and J?, nemorosus ; this character is difficult to lay hold of, being quite 

 comparative. 1 think, however, that the joint will be found to be, as 

 generally stated, nearer the base in the latter than in the former ; 

 sometimes it is certainly quite close to the stem in nemorosus, so 

 that when the fruit falls, carrying the distal portion of the pedicel 

 with it, the remaining stump is a mere tubercle, instead of, as in con- 

 glomeratus usually, a distinct stalk. The colour of the unopened 

 anthers in the young flowers is also said to afford a good distinctive 

 character, being pale cream-coloured in conglomeratus and pale (bright) 

 sulphur yellow in nemorosus. 



It may be convenient to give references to the published figures 

 of these two species, in continuation of notices of other British species 

 which have been from time to time printed in this Journal. 



b2 



