THE NATURAL HISTORY SURVEY. 347 



The genitalia is very interesting; the ovotestis is very long 

 and is buried in the folds of the liver; the ovisperm duct is 

 very long and narrow and enters the uterus near the upper 

 part; the albuminiparous gland is long-oval in shape and has a 

 long, narrow duct which empties into the uterus near the ovi- 

 sperm duct; the receptaculum seminis is long and rather thick, 



FIG. 130. 



Genitalia of VALVATA CRISTATA. (Bronn, Klassen und Ordnungen 

 der Weichthiere, Malacozoa, pi. xxxviii, Fig. 23.) dal, duct from albu- 

 miniparous gland; dh, ovisperm duct; gal, albuminiparous gland; gh,ovo- 

 testis; p, penis; rs, receptaculum seminis; ut, uterus; vd, vas deferens. 



and the upper part is attached to the albuminiparous gland; 

 the uterus is very large and very wide, narrowing toward the 

 opening (atrium); the vas deferens is very short, narrow, and 

 enters the uterus near the lower third; the penis is very large, 

 long, thick and fleshy, and appears like a third tentacle on the 

 right side of the animal, behind the right tentacle (Fig. 130). 



GENUS VALVATA O. F. Muller. 



Shell, Animal and Dentition: As in the family. 

 Distribution: World-wide. 



KEY TO SPECIES OF VALVATA. 



a. Shell with rounded whorls. . , sincera 



