6 BOTANICAL GAZETTE | JULY 
by Meunier, and for the sake of simplicity have been omitted 
from nearly all drawings in the present paper. We may note, 
however, that the origin of the trichome from a portion cut 
from the acroscopic end of an epidermal cell is practically the 
same as in Marsilia, though the regularity is not so striking. 2 
As is well known ( Bischoff 28), the mature leaf of Pilularia a 
has no lamina whatever. We may consider it as quite probable, — 
however, that the immediate ancestors of Pilularia and Marsilia a 
had leaves possessing a lamina, which still persists in the latter 
genus, and we might expect to find some remnant or trace of | 
this in Pilularia in the mode of division of the segments if not — 
in the outward form. Keeping in mind then the mode of devel-— 
opment of the lamina in Marsilia, by the continued activity of - 
the marginal cells near the apex of the leaf, many segments in — 
this region of the leaf of Pilularia were examined in search of — 
any irregularity in the formation of cell walls, or of continued 
activity of the marginal cells. The results were always negative 
and we must therefore conclude that the development of the 
of Pilularia gives no indication that it has ever possessed a 
amina. 
THE SPOROCARP, 
The sporocarp of Pilularia was considered by Hofmeiste 
(’62) as a modified branch arising as an accessory bud at t 
base of the leaf. Alexander Braun (70) and his pupil Russow 
(72) dissent from this view, and on theoretical grounds consider — 
ita segment or branch of the leaf; while Juranyi (’80) a 
Goebel (’82) confirm this latter view as a result of the stud 
the development of the sporocarp and the relation of its tis 
to those of the neighboring leaf. Meunier (87) , however, wh 
holding that the latter view is probably the correct one, thin! 
the evidence adduced is at fault, as the vascular bundle of r 
Sporocarp, according to his observations, does not fuse first ’ 
that of the leaf, but with that of the stem itself. He then poin 
out that the best evidence for this view will be the proof 
both arise from the single apical cell of a foliar structure at 
