REPRODUCTIVE SYSTEM. 389 
duct towards the head along a common duct, but not at the 
same time. Moreover, their paths are different, for the 
portion of the duct down which the ova travel is much 
plaited, while the path which the spermatozoa follow is a 
Fic. 209.—Dissection of snail. 
T., Short horn; 77., long horn with eye; WV., cerebral ganglia; S.G., 
salivary glands on the crop; #., foot; M., columellar muscle; .C., 
visceral coil; O.7., ovotestis; V., ventricle of heart; R. rectum; U., 
ureter; B.V., blood vessels returning to the auricle from the mantle; 
A., pulmonary aperture ; J7A., edge of the mantle. 
less prominent groove, incompletely separated from the 
other. Both paths are glandular, and the glands on the 
male side are often called prostatic. 
(e) At the base of this common duct, a distinct vas 
deferens diverges to the left and leads into a muscular fezs, 
