24 COCCOPHYCE. 
a protoplasmic gonosphere, coloured by chlorophyll, containing numerous 
starch granules ; it presents at one point of the periphery very often a 
clear spot. The gonosphere is loosely enclosed by the several (3-6) con- 
centric gelatinous (as it were swollen or expanded) membranes. Such 
oogonia lie either several together, forming a moniliform chain, or they 
present themselves in the middle of a series of antheridia, or between 
unaltered vegetative joints, upon which, further on, may abut antheridia. 
Cylindrocapsa is thus monoicous. At both poles of the oogoninm the 
coats are produced into a short cylindrical process ; adjoining processes 
are mutually apposed. The size of the oogonia varies; it may reach 
-042 mm., the gonosphere ‘024 mm. 
“ The antheridia are discoid or spheroidal little cells, like the oogonia 
possessing a multi-laminated coat, they may form a long series or little 
groups of pairs ; they are often enveloped in twos or fours by numerous 
lamingz. The contents are clear reddish yellow. The male cells (like 
the vegetative) are formed by binary division of the mother joint, with 
the distinction that they cease to grow, remain smaller, and gradually 
assume the yellowish red colour. Each antheridium developes by divi- 
sion of its contents two spermatozoids. At maturity they are ejected 
with a jerk ; when free, they lie for a while motionless enclosed in their 
gelatinous envelope. Presently they assume a tremulous motion, at last 
bursting the vesicle and swimming about. They are protoplasmic fasi- 
form bodies of about 015 mm. in length, contents sparing, yellowish 
red; at the anterior hyaline point are borne two flagella, below which 
are two minute pulsating vacuoles. 
“ Shortly after their exit they are to be found in the neighbourhood 
of the oogonia. The whole cavity of the oogonium becomes pushed out 
laterally, dissolving and leaving an opening at the apex of the expansion. 
The spermatozoids seem now to be no way aimless in their movements, 
their whole object being seemingly to effect a penetration; with great 
energy they drive against the wall, and retreat, and so persist for hours, 
until at last the movement ceases, and they shrink into formless little 
masses. The actual confluence of the spermatozoid with the gonosphere 
was not observed, but the conclusion drawn by the author seems to be 
legitimate. 
“The next change consists in the appearance of a thick gelatinous 
stratum directly on the surface of the gonosphere, which soon hardens 
into a doubly contoured membrane. After some days the chlorophyll with 
the starch granules gradually disappear, becoming replaced by the 
reddish-yellow oily substance. In this way we obtain from the gonosphere 
an oospore surrounded by the mucous layers of the oogonium. The 
author could never see any further development ; they lasted the whole 
autumn and winter without the slightest alteration. 
“In some instances the gonospheres on having become enclosed by 
the gelatinous envelope began to germinate; they divided into two 
segments, each then becoming clothed by its own gelatinous envelope, 
and soon divisions followed just as in the ordinary vegetative joints. 
The author supposes that these still green gonospheres could not have 
been fertilized, and that only the latter pass over into a state of rest.” 
—Quart. Journ. Micr. Sci., 1877, p. 181. 
Genus 17. HYDRURUS. dg. (1824.) 
Thallus adnate, gelatinous, more or less firm, tubular, elon- 
gated (2-4-12 inches long), sometimes variously divided, sticky, 
surface naked or densely covered with delicate fibres, which at 
times are fasciculate. Cells in the beginning globose, or sub- 
