26 ENGLISH BOTANY. 
as the leaves opposite to which they spring, when the latter are of 
the submerged form; but when the peduncles spring from floating 
leaves, the difference in length is not so great. Petals about 
twice as long as the calyx, obov ate, 7- to 9- saniail white with a 
yellow base, spreading like the rays of a star when fully expanded. 
Achenes generally in many more rows (often ten or twelve) than in 
any of the previous species, and, therefore, much more numerous, 
amounting even to as many as 50 or 100 carpels on each receptacle, 
pale yellowish olive, with the inner side straight from the base for 
about two-thirds, and thence more or less convex to the apiculus 
formed by the persistent base of the style, the outer side curved, 
usually much rounded towards the apex, so that the ¢ carpel may be 
termed inflated. Receptacle elongate, with the hairs much more 
distant than in R. aquatilis. 
There can be little difficulty in distinguishing this plant from 
KR. aquatilis on account of the longer peduncles; much more 
numerous achenes, in about twice or more times as many rows 
very closely packed in a head, which tapers somewhat towards the 
apex; the longer style, and the flattened stigma. 
R. confusus appears to be simply a variety, as there is no cha- 
racter by which it can be separated, except that the stamens are 
longer than the head of pistils. The achenes vary in shape quite 
independently of the length of the stamens; and the narrowing of 
the apex of the achene, which is given as one of the distinguishing 
features of R. confusus, is quite as often seen in plants which have 
the normal form of R. Baudotii in other respects. Indeed, the 
inflated and attenuated form of achenes may be met with on the 
same individual. 
A small form, without floating leaves, with the peduncles not 
much exceeding the submerged leaves, approaches closely the 
habit of R. trichophyllus, and in the dried state is occasionally 
difficult to distinguish from that. 
%. marinus (Fries), which occurs in the Baltic, but has not 
been observed in Britain, is a variety, or perhaps a sub-species, of 
lt. Baudotii, distinguished by the apparently constant absence of 
floating leaves, by having the dissected leaves sessile with fewer 
segments, and the achenes more convex on the inner side near the 
tip, so that the persistent base of the style forms an apiculus which 
is nearly central on the apex of the carpel; but I have seen ex- 
amples of R. Baudotii and R. confusus with carpels precisely similar 
to those of Fries’ specimens of his Herb. Norm. in the Hookerian 
Herbarium. Fries describes the achenes as keeled; but R. Baudotii 
and, indeed, most of the other species of this section, are liable to 
have a false keel produced by the shrinking of the pericarp in 
drying. This sub-species is mentioned here, as it is not at all 
unlikely to occur in brackish water on the Scottish coast. 
Baudot’s Water Crowfoot. 
