in R. maritima more or less short, since the pollination 
takes place subaquatically, in general already before the 
spike’s shooting out from the involucral leaves. In R. spi- 
ralis the peduncle stretches out to reach the surface of the 
water, since the pollination must there take place. This is 
decidedly proterandric, that not so. In the R. spiralis the 
anthers have an oval form and the pollengrains are 4—5 
times as long as broad. In R. maritima those are more 
rounded and these shorter, 3—4 times the width. The fruit 
is also different. In R. spiralis longer, 2,5 à 2,8 mm., more 
elongated and with more conspicuous rostrum ; in R. mar. 
shorter, 1,5—2 mm. and with shorter rostrum (especially invar, 
brevirostris). To this also comes a significant anatomic 
difference (see below!). All these circumstances, compared 
with similar facts in the allied genus Potamogeton, force us 
to give both Ruppia spiralis and maritima the higher rank 
of species and not only of subspecies. As to R. brachypus, 
it presents the very same leaf-apex and the same stem — 
and leaf- anatomy as P. maritima , and, for the rest, very 
slight and inconstant properties, and cannot specifically be 
separated from that species. 
The European forms of R. maritima usually have 
rather short peduncles. A form from Asia gathered by 
Ove Poulsen at Buchara, in a saline pond, in 1898 ( 12 , m), 
however, has somewhat longer peduncles (3 — 6 cm. or more). 
We propose to name it var. longipes. In The United States 
of America this variety seems to be the commonest Ritp- 
pia. It appears in two forms: one with more prominent, 
thin beak, forma aculeata n. f., belonging chiefly, as I think, 
to the eastern States, and the other with an almost sessile 
stigma (Rydberg, 1. c.), spreading westward: forma pecti- 
nata Rydb., as sp.). This variety forms the one extremity, 
the var. brevirostris Ag. (R. brachypus Gay) forms the 
other, with very short peduncle. The length of the peduncles 
in this species, at all events, is of no or less importance 
tor the plant concerning the pollination. It mostly fruits 
