174 PRINGSHEIM, ON ALG. 
two sexes in some fresh-water Algee—the Conferve, in which 
their existence had previously been scarcely suspected. It is 
true that the motions of certain spores (zoospores) at matu- 
rity had been remarked, and that this motion was caused 
by the action of vibratile cilia, with which they are fur- 
nished. Their germination even had been traced. But as to 
antherogoids, or male organs, I know of no observer before 
M. Pringsheim who had noticed them in the lower Alge, 
and particularly in Cidogonium, one of the subdivisions of the 
genus Conferva of Linnzus. 
“Nothing is more marvellous than the phenomena attend- 
ing the act of fecundation of these plants. The sexual appa- 
ratus, the metamorphoses that the androspore or male organ 
undergoes, and the act of fecundation itself, seem so many 
facts contrived on purpose to excite our utmost wonder and 
admiration. 
“The species of Gidogonium are simple, filamentous Alge, 
living in fresh water, and composed of cylindrical cells placed 
end to end in a single series. They present this peculiarity, 
that. the greatest number of species are marked by annular 
striz placed on certain special cells. In one of these cells, 
at the time of reproduction, the contents accumulate, become 
condensed and distended, and sometimes produce zoospores ; 
sometimes a single spore, which is detached, and falls to the 
bottom of the water, when mature, to perpetuate the plant. 
“This is all that was formerly known. We were completely 
ignorant of what indueed the successive changes that the spore 
underwent before it was detached. This is what M. Pring- 
sheim has observed. In the same filament which produces 
the female cells destined to propagate the plant, others may 
be observed, generally shorter, in which bodies are developed 
which might be compared to antheridia, since they enclose 
the antherozoids. These bodies, ovoid, crowned with vibra- 
tile cilia, and called by the author androspores* (Andro- 
sporen), very closely resemble zoospores, but are very 
differently organized. Escaping from the vesicle which in- 
closes them, these androspores attach themselves at a deter- 
minate moment firmly on the female cell. The filament, 
whole and unbroken until now, opens its joints at the level 
of one of the striz like a soap-box, to allow of the protrusion 
of the membrane containing the gonimic matter or the 
potential spore. This protruding portion, which the author 
calls fecundating tube (Befruchtungschlauch), is perforated 
by a round opening at the spot where the androspore had 
s, * These are the organs which have been termed Microgonidia by Alex. 
raun, 
