1881. ] Variations in a Copepod Crustacean. 697 
In the male the vas deferens can be distinguished into three dis- 
tinct sections, each of them performing a different 
function. The glandular cells of the walls of the 
_c first section secrete a viscid, gluey substance, a sort 
of cement into which, coming from the testis and 
passing through the posterior ter- 
minus of the vas deferens, the elon- 
Fic. 12,. gate (in Diaptomus) zoosperms en- 
Front view of ter, forming a long narrow string. 
rag 5 he The diameter of the first section is 
racic segment nearly of equal width in its entire 
of female and ee 
part of thefirss 0ngth. The second section is more Sa 
being eer dilated anteriorly, rounded and ta- Diapromus sanguine- 
two spermato. Pering posteriorly. Here we find a %, ria gt mea 
Phores, c, ge central, voluminously swelled mass, 
‘the other en- the above mentioned homogeneous glue-mass, periph- 
‘rely empty. ¢rically surrounded with a layer of densely packed 
zoosperms, which but loosely fit into innumerable roundish lodges 
or hives, the latter constituting the interior of the partly perfected 
exterior spermatophore capsule. The formation of the latter be- 
gan probably already in the first section, since the two sections | 
do not functionally differ from each other. This still imperfect 
spermatophore enters immediately into the third and last section 
of the vas deferens as soon as the last perfect one has just left the 
male genital orifice. 
A number of zodsperms in the posterior rounded terminus of 
the Spermatophore act as abortive or expelling factors, becoming 
first granulated toward the perfection of the spermatophore, and, 
through the endosmotic absorption of water, several of them co- 
alesce with a number of cellular vesicles like soap-bubbles (polyg- 
onal in Diaptomus). The expelling cells gradually swell, pressing 
the central glue-mass into the middle of the spermatophore, and 
first become nucleate and then plain. Through the further increase 
of these expelling cells, the central glue-mass is more and more 
compressed and slowly moves toward and out of the narrow ter- 
minus of the spermatophore, and in oozing out forms a saussage- 
like body, by means of which, in copulation, the spermatophore 
is glued beneath the valvule of the female genital orifice. Into 
the center of this mass follows the remainder of the zodsperms, 
the latter being perfectly surrounded by the former, forming a 
