but I possess specimens from Swan River {Drummond) ancl from 
Tasmania {Mr. Ronald Gunn). 
A very aquatic variety, with long narrow cauclex and leaves, 
partially at least floating upon the water, but without fructifi¬ 
cation, has been called P.natans by Merat in his FI. Paris. The 
same is found in Smoland by Fries, and is his P. globulifera , 
var .jluitans. 
A very small and extremely delicate Pilularia is found in Al¬ 
geria, of which I possess native specimens fromBalansa (n. 210), 
and others from Professor Braun, “ e seminibus culta in Horto 
Friburgensi, 1848.” The leaves scarcely exceed an inch in length, 
and are as delicate as the most filiform Diva, with fructifications 
small in proportion. It is the P. minuta , Durieu, in Explor. 
Scientif. de L’Algerie, Fartie Bot. t. 88, unfortunately unaccom¬ 
panied with any description ; so that, except the smaller size and 
the “ two-celled ” fruit, it is difficult to say how it is to be dis¬ 
tinguished from the European species. 
P. globulifera has a slender, creeping, filiform, branched cau - 
dex or rhizome , bearing leaves circinate in vernation, on the 
upper side, single or one to two, three, or four in fascicles, and 
slender fibrous root beneath, opposite to the insertion of the 
leaves, which are also filiform, yet tapering above, very slender. 
From the cau dex at the base of the leaf the globose receptacle 
appears on a very short footstalk, very hairy at first, at length 
nearly glabrous; this is subcrustaceous, four-celled, opening at 
the top by four valves: in the inside, and corresponding with 
each valve, is a fleshy receptacle, bearing two kinds of membra¬ 
naceous pellucid sacs , the upper ones {antheridia) pear-shaped, 
numerous, including subglobose granules; the lower part of the 
cell is occupied by larger membranaceous sacs, including a sub- 
globose glandular body apparently floating in it, slightly con¬ 
stricted near the middle, and crowned with a conical point. 
This is filled with a grumose substance, composed of particles 
which appear, under the high power of a microscope, as if formed 
by a union of three to four granules. Numerous microscopic 
figures of the contents of these two kinds of fructifications have 
been published by different authors, but they are by no means in 
harmony with each other; and we have yet much to learn of 
their true organization and uses in the economy of the plant. 
Plate 57. Fertile plant of Pilularia globulifera, Linn .,—natural size. Fig’. 1. 
Portion of a cauclex, with leaves and a receptacle. 2. Young receptacle. 3. Per¬ 
fect receptacle, cut through vertically, showing the two kinds of fructifications. 
4. Transverse section of a receptacle. 5. A young, and 6. Mature sac from 
the lower part of the cell, generally considered to be the female fructification. 
7. Sac from the upper part of the cell, considered to be analogous to stamen. 
8. 3—4-lobed granules from within the sac :—all more or less magnified. 
