MOLLUSCA. 



277 



FIG. 242. Top-shell (Turbo marmo- 

 r<itu); one fourth natural size. 

 China seas. 



FIG. 243. Strombus gigcu, or "Winged- 

 shell ;" one fifth natural size. Weat 

 Indies. 



FIG. 244. Paludina, a Fresh-water 

 Snail. 



FIG. 245. Key-hole Limpet (Fissuretta 

 listen). West Indies. 



FIG. 246. Ea" -shell (H. tuberculata), aud Dog-whelk (Xasaa retu-ulata). England. 



