198 POPULAR BurrisH conchology. 



of the outer lip with the body. Some of them have^ others 

 have not, opercula. As far as the shells are concerned, we 

 may give some notion of their affinity with the Cones by 

 saying, that some Tleuroiomce are like some Cones, and some 

 Mangelice are like some Pleiirotomce. Mr. Arthur Adams, 

 in his account of the moUusca seen or collected during the 

 voyage of the Samarang, mentions that no fewer than forty- 

 three species of these brisk little molluscs were found among 

 the islands of the East Indian Archipelago. That gentle- 

 man informs us that their " favourite locality is coarse, loose 

 sand, either in sand-patches on the reefs, or under stones in 

 deep water outside the reefs, or in still deeper water, where 

 the sand is mixed with mud. . . . The species which 

 live at considerable depths are dark-coloured, and strongly 

 ribbed ; those that prefer the loose sands are generally gra- 

 nulated, finely ribbed or cancellated, and of a light brown 

 colour ; while light-coloured species, which are seen crawling 

 over mud flats, are often covered with a fuscous epidermis." 

 The IlangeUcB have subulate tentacles, meeting at the 

 base, with eyes placed on the truncated ends of thickenings 

 at various heights. The proboscis is retractile, and the 

 siphon of the mantle is produced beyond the canal of the 

 shell. The foot is more or less truncated in front, some- 



