Marshall—A Parasitic Ostracod. 
133 
Male :—My knowledge of the male productive organs is very 
fragmentary. In none of the series of sections, did I succeed in 
getting a clear view of the relation of the parts to each other 1 or 
he sure even that they all had been made out. All the parts 
were paired, the vas-defferentia undoubtedly uniting some¬ 
where in the copulatory apparatus. The testis, PL XII, fig. 
20, appears to be a single wide lobe containing cells, in the dif¬ 
ferent stages of spermatogenesis. The posterior part of the 
testis unites with a slightly larger portion which I took to be a 
seminal vesicle, principally from the fact that within it the cells 
did not show the. different forms noticeable in the testis* and 
also from a failure to differentiate in it the various zones. 
Both the testis and the seminal vesicle before their 1 union pass 
into a peculiar ovoid body. It is slightly inclined, the poster¬ 
ior end being somewhat higher than the anterior, and appears 
filled with a granular mass resembling very much the yolk in 
the eggs. Through this body, from, end to end, runs* the vas 
deferens which upon its exit swells* slightly, and beginning to 
turn ventrad enters the base 1 of the copulatory apparatus. In 
nearly all specimens it was filled with spermatozoa,, but I was 
unable to trace it to* its* exit. 
COPULALATORY APPARATUS. 
Kaufmann (7) has already called attention to* thei large size 
of this apparatus in the Cytheridae , it being at first sight; one of 
the most noticeable parts. It is, very complicated, consisting of 
a number of chitinous pieces, both main, parts and connecting 
strands, and a system of muscles which are nearly all of them 
connected entirely with the organ. All the parts are! paired. 
Zenker (19) divides the entire apparatus into three parts: 
1. Basal piece to* join inner and outer parts. 
2. Copulatory tube. 
3. Clasping apparatus. 
In Entocythere the basal piece is by far the largest part 
(shown in the figure as two pieces which are, however, firmly 
united) its length being more than half the height of the* ani¬ 
mal, PI. XI, fig. 10. The anterior half has a rounded surface 
