PACKARD.] REPRODUCTIVE HABITS OF BRANCHIOPODIDA. 421 
abdominal segment; it broadens rather suddenly, and reaches up in the 
form of a whitish tape to near the middle of the united genital segments, 
where it expands and suddenly contracts again into a more cylindrical, 
narrow string, the vas deferens, for but a short distance, after which 
follows a second larger expansion, representing the seminal vesicle, 
bending knee-shaped down and outward, and after again narrowing to 
a tubular duct, the ductus ejaculatorius, is interrupted several times 
with what I take to be accessory glands, just before entering the termi- 
nal extensile portion, the complicated muscular apparatus. The cirri 
are non-perforated, and supplied with minute hooklets (as in Branch- 
ipus gruber and B. stagnalis). At its base several powerful muscles 
insert themselves, the musculi retrahentes. 
The anterior (upper) end of the testicle is in younger individuals 
of the red Eubranchipus and pale race A an obliquely cut-off tip, as 
Spangenberg" figures it in Branchipus stagnalis, but in set B no trace of 
this prolongation, either in younger or older individuals, can be seen, 
thus resembling Dr. F. Leydig’s figure.” 
The complicated muscle-apparatus, described and figured by Dr. H. 
Nietsche? (Branch. grubei), occurs also in Eubranchipus and its pale 
races, the cirrus being likewise non-perforated and hooked. Chitinou 
papilli (Branchipus grubet) and spines (Branchipus stagnalis) I could not 
observe. 
(2.) Female organs (pale).—The spirally-wound ovary extends in set B 
(and A?) not only with its posterior end into the penultimate post-ab- 
dominal segment (as in red Eubranchipus, Branchipus grubei and B. 
stagnalis), but also with the anterior (upper) end up to the limit of the 
fourth last pair of branchipeds.* 
I have often observed in living specimens from 5 to 6 plasmatic eggs 
of a turbid white color in the upper ovarial string, but then the post- 
abdominal section on the same side was empty, or the reverse. I also 
occasionally observed both sections, the anterior and posterior, full of 
plasmatic eggs, and at the moment ot entering the oviduct by jerks from 
the posterior section, the anterior portion of the ovary remained filled 
for some time until also emptied into the oviduct. The emptying of 
the anterior section usually took place also on putting live specimens 
into alcohol, and in this instance the posterior portion remained filled. 
The eggs of the anterior section have the same form and appearance as 
those of the posterior. 
Another notable fact is a very short, transverse, tubular anastomosis 
within the sixth and near the seventh post-abdominal segment. This I 
have not seen to occur in the females of red Hubranchipus, neither have I 
found it in all females of the pale races. The anastomosis passes 
under (ventrally) the intestinal tract, and is sometimes filled with 2 or 3 
plasmatic eggs. It is about 1,'™™ long, narrower than the lateral ova- 
ries; its skin apparently muscular, since the eggs are squeezed side- 
ways out into the lateral strings when: live specimens are placed in 
alcohol, or when, by a jerk, the eggs enter the oviduct. 
1 Zur Kenntniss von Branchipus stagnalis von Dr. Friedrich Spangenberg, mit Tafel 
I-III. Zeitsch. f. wiss. Zoologie, xxv; Supplementheft, 1875, Fig. 28, t. 
* Dr. Franz Leydig, ‘‘ Ueber Artemia salina und Branchipus stagnalis.” Zeit. f. wiss. 
Zool. iii, 1851, Taf. VIII. 
5 Dr. Heinrich Nitsche, ‘‘Ueber die Geischlechtsorgane von Branch. Grubei von Dy- 
bowsky” in Zeit. f. wiss. Zool., xxv, page 281, Taf. XXII. 
4Schmankewitsch doubts whether or not some of the branchiped-bearing body-seg- 
ments belong to the post-abdomen. The peculiar arrangement of the ovary here seems 
to give support to this assumption. See Zeit. f. wiss. Zool. 1875, pages 114 and 115; 
also Spangenberg, in op. cit. pages 8 and 9; and Nietsche in op. cit. 
ee anastomosis indicates a sexual relationship with certain Schizopod and Cope- 
poda. 
