BATRACHOSPERMUM, 11 7 
With the process of fecundation as the primary object in view, 
Batrachospermum has been recently studied by Davis (’96), Schmidle 
(’99), and Osterhout (1900). As regards the cytological details 
bearing upon fecundation the work of Osterhout seems to have been 
the most thorough. 
The well known female sexual organ, the carpogonium, of Batra- 
chospermum, is a single cell consisting of a somewhat flask-shaped 
basal part, the trichophore, in which is the egg-nucleus, connected by 
@ narrow neck to the elongated, cylindrical or club-shaped, upper 
part, the trichogyne (Fig. 45, B). In B. doryanum Sirodot, the 
species studied by Osterhout, the chromatophore of the trichophore 
is continued into the trichogyne. The structure of the nucleus is 
the same as that of higher plants. The spermatia are globular cells 
with one nucleus and a 
reduced chromatophore 
in younger stages (Fig. 
45, A). 
Fie. 45.—Sexual organs of Batrachospermum boryanum 
Sirodot.—(After Osterhout.) 
A, antheridium with one nucleus and vacuolate cytoplasm, 
B, mature carpogonium before fe dation. 
C, spermatium has copulated with trichogyne of carpogo- 
nium ; cytoplasmic fusion has taken place, but nucleus 
is still in spermatium; egg-nucleus lies in tricho- 
phore. 
Schmidle (’99), whose observations were made chiefly upon 2. 
bohner?, agrees with Osterhout as regards the structure of the carpo- 
gonium, but in the spermatia of this species he finds, almost invariably, 
two nuclei. Davis (’96), differing from both Schmidle and Osterhout, 
claims that in B. moniléforme Roth., B. cwrulescens Sirodot, and 
B. boryanum, the trichogyne is a distinct cell possessing a well defined 
nucleus and chromophore, and connected with the trichophore by a 
strand of protoplasm. The methods used by Davis at the time were 
inadequate for the better differentiation of the nucleus, and his con- 
.clusion is in all probability incorrect. 
The copulation of the spermatia with the trichogyne and the fusion 
of the sexual nuclei is as follows: One to several spermatia, which are 
now provided with a cell-wall, become attached to the trichogyne 
chiefly near the end (Fig. 45, C, and Fig. 46,D,E). After the disso- 
lution of the cell-membranes at the point of contact the nucleus of the 
spermatium enters the trichogyne and passes down through it into the 
base of the carpogonium. The canal between the trichogyne and the 
