2 5 2 THE TANGANYIKA PROBLEM. 



floor, between the folds of which the curiously rectangular 

 orifice of a single bile duct opens. Besides this stomachic 

 chamber there is an anterior diverticulum into which the 

 large stomach opens by a tubular aperture, through which 

 a bristle may be passed, and in this anterior stomachic 

 chamber there lies an almost spherical crystalline style. 



Fig- 35- — The animal Nassopsis nassa from the dorsal 

 aspect. The mantle has been cut open from above, 

 and the radular sac exposed. 



The intestine passes out of the stomach beneath the tubular 

 aperture between the posterior and anterior stomachic 

 chambers, as indicated in the drawing on page 251. The 

 intestine is coiled in the manner seen on page 251, and 

 towards its rectal extremity it contains a number of 

 glandular folds and striae. 



The liver is large, and occupies the lower two-thirds of 



