668 THE AMERICAN NATURALIST.. (Vor. XXXIX. 
is very large. The receptaculum seminis is rather small, pyri- 



Fic. 3.— Genitalia of Zymnea palustris afpressa. 
form, and is connected with the lower part of the vagina bya 
long, narrow duct. Both male and female genitalia are supplied 

Fic. 4.— Lymnea palustris appressa, 
showing position of oviduct, prostate, 
and ovisperm duct. 
of the female organs, 
with nerves, the former from the 
cerebral ganglion and the latter 
from the right visceral ganglion. 
The organs are very brightly col- 
ored, the albuminiparous gland, ovi- 
duct, uterus, and receptaculum 
seminis being orange, the prostate 
orange shading into black at its in- 
sertion, the vagina blackish white, 
and the penis-sac flesh-colored. The 
ovotestis is white, as are also the 
muscles, vas deferens, and ducts 
The ganglia are bright pink or orange. 
