4 
18 ENGLISH BOTANY. 
2 or 83 teeth or short lobes at the apex. Stipules broad, half-adnate, 
with large rounded auricles. Peduncles long, slightly tapering 
upwards. Petals much larger than the calyx, often in two rows, 
Stamens shorter than the head of pistils. Stigma cylindrical. 
Achenes (often abortive) loosely packed in a globular head; their 
inner edge straight, their outer curved. Receptacle at length 
glabrous, 
Var. a. peucedanifolius. 
R. peucedanifolius, Desf Fl. Atl. Vol. I. p. 449. 
Stem stout, leaves very long, petiolate. Peduncles usually 
shorter than the leaves from which they spring. Petals broadly 
obovate. 
?P Var. 6. Bachit. 
R. Bachii, Wirtg. P’. Schultz, Arch. de Fl. Vol. I. p. 292. 
Stem very slender. Leaves much shorter than in var. a, and 
almost sessile. Peduncles longer than the leaves from which they 
spring. Petals narrowly obovate. 
Rather rare. In canals and running streams generally dis- 
tributed in England; very local in Scotland, where the Whitadder 
in Berwickshire appears to be its northern limit. The variety PB 
occurs in that river and in Staffordshire. This species is included 
in Mr. Moore’s list of Irish plants. 
England, Scotland, Ireland. Perennial. Summer. 
Stem floating, often very long, branched. Leaves sometimes a 
foot long; the lower ones usually with long stalks, the upper some- 
times nearly, or quite, sessile; and in # all the leaves are often 
so. Leaves trifurcate, with the primary segments sub-equal; these 
are several times forked, and their long, comparatively rigid seg- 
ments (which are much fewer in number than in the leaves of the 
other species) form a slender tassel-like tuft. On mud left by the 
water the leaves are much shorter, and the segments broader and 
more fleshy in texture. Peduncles very thick in a, slender in £. 
Petals large, white, often more than 5, with a yellow base. Nectary 
with a rather elongate margin. Stamens numerous. Style short. 
Receptacle shortly conical; at first hispid, but glabrous when the 
fruit is ripe. Achenes loosely packed in a small globular head, 
obovate-ovoid, compressed, with very prominent transverse wrinkles; 
inner margin nearly straight, tipped by the persistent base of the 
style; outer edge semicircular, very blunt at the apex, where it 
bulges out beyond the point where the style is inserted, which thus 
appears to be lateral. 
