28 
show them to be so markedly indented as to amount to a very dis- 
tinct lobation. A vas ellerens rises from each testicle: that from 
the jx)Sterior testicle appears to spring from the right dorsolateral 
aspect and passes cephalad between the anterior testicle and the 
right intestinal cecum: that from the anterior testicle springs from 
near the left margin of its cephalic aspect, and passing cephalad. it 
unites with its fellow beneath the esophageal fork to form the vas 
deferens. In their course they both become dilated and contain 
masses of spermatozoa. The vas deferens winds its way cephalo- 
ventrad in close relation with the coils of the uterus, and opens to the 
exterior by a pore coromon with the opening of the female duct. Dur- 
ing its course, several distinct portions may be more or less clearly 
recognized, but not with equal ease in all specimens. ^lost favorable 
for interpretation seem to be specimens with ftiUy extrtided. mush- 
room-like genital papilla. The centripetal portion of the vas repre- 
sents the vesicula seminalis. which is coiled up into a more or less 
compact mass and which, when filled with spermatozoa, may present 
quite a large lumen. Xext. centriftigally. comes the pars muscularis ; 
this is provided with distinct muscidar fibei's. but is not developed to 
such an extent as seen in certain other amphistomes. for instance in 
Paramphlstomum caUcophonim. The duct then becomes rather 
suddenly enlarged, is surrounded by a less prominent layer of mus- 
cular tissue, is provided with a considerable numl^er of cells re- 
sembling those found in the pars prostatica of other amphistomes. 
but much less striking in their development and arrangement, so 
that were it not for analog^', one would probably hesitate to interpret 
them as prostatic cells : the lumen of this portion may contain large 
masses of spermatozoa, s^d that in general ellect the structure reminds 
the observer of the vesicida seminalis interna described for certain 
species possessing a ciriuis pouch. As this portion narrows centri- 
ftigally. the prostatic-like cells at first seem to increase, then to de- 
crease in number, until they finally disappear. Then follows a por- 
tion of the male canal, of narrower diameter, but still remaining 
larger than the corresponding portion of the female duct, and ap- 
parently devoid of both muscles and prostatic cells : this apparently 
represents the ductus ejaculatorius and opens into such a short ductus 
hermaphroditicus that the latter almost represents only a pore com- 
mon to the male and the female canals. 
Female organs: Caudad of the testicles, the interspace i^etween the 
intestinal ceca contains coils of the uterus, the ovary, and the shell 
gland. The ovaiy is a somewhat globular body, veiy much smaller 
than either testicle : it is placed a little to the left of the median line, 
near the end of one of the intestinal ceca. and somewhat alx)ve 
I cephalad of) the anterior margin of the acetabulum. From its 
dorsoinferior (caudal) aspect springs the oviduct which curves can- 
