454 



THE OCEAN WORLD. 



branchial cavity. The foot is large, and furnished with a horny 

 operculum. 



These animals keep near the shore, in shallow water. They walk 



Fig. 279. Cassis glauca 

 (Linnaeus). 



Fig. 280. Cassis rufa Fig. 281. Cassis canaliculate 



(Linnseus). (Brugieres). 



Figs. 282 and 283. Cassis Madagascariensis (Lamarck). 



slowly, and often sink themselves into the sand, where they prey 

 upon small bivalves. There are not very many species ; but sped* 

 mens from the Indian Ocean are often large and beautifully marked. 



