204 



MOLLUSKS: GASTEROPODS. 



Fig. 388. Cerithiura. 

 Much reduced. Molucca. 



Fig. 389. Melania. 

 Western States. 



Fig. 390. lo. 

 Southern States. 



Fig. 391. Tower- 

 Shell, or Turritella. 

 West Indies. 



Fig. 392. Wentle-trap. 

 Reduced. China. 



Fig. 393. Worm- 

 Shell, or Vermetus. 

 West Indies. 



Fig. 394. Fig. 395. 

 Periwinkle, Lacuna, 

 or Litorina. 



Fig. 396. 

 Valvata. 

 IT. States. 



Fig. 397. River Snail-Shell, 

 or Paludina. United States. 



