CHAPTER V: THE TRITONS AND FROG SHELLS 



Family TRiTONiDiE 



Shell spiral, thick, with one or two varices to each whorl; 

 aperture round, with thick Hps, and anterior canal; operculum 

 present; mantle enclosed; foot small,; siphon short; lingual 

 ribbon set with seven rows of teeth; eyes on tentacles. 



A large tropical family of three genera allied to Muricidae 

 on one side, and Doliidae on the other. They subsist upon de- 

 caying animal matter and live from low water to fifty fathoms 

 depth. 



Genus TRITON, Montf. 



Shell ovate or oblong, with prominent elevated spire, ribbed 

 and crossed by varices, usually few, remote, and non-continuous; 

 columella smooth, wrinkled or noduled; outer lip thick, and 

 scalloped or toothed within; canal long or short, turned up; 

 operculum horny, ovate or annular, with nucleus marginal. 



A handsome tropical genus of about 150 species, including 

 one that reaches 18 inches in length — "almost the largest of gas- 

 teropod mollusks," writes Tryon. Some species have world- 

 wide distribution, accounted for by the fact that the young are 

 pelagic and free-swimming, very different creatures from the 

 staid adult Tritons. The metamorphosis occurs some time after 

 hatching. 



"The Tritons are shells of much more solid structure than 

 the Murices or Ranellse, and of much more simple growth. They 

 are not furnished with any spines nor haye they any ramified 

 branches like the Murices ; the rude manner in which the whorls 

 are convoluted seems rather to indicate that their animal inhabi- 

 tant, though possessing abundant power of calcification, is of 

 somewhat -sluggish growth." — Reeve. 



A very tough skin covered with hairs or bristles protects 

 the shell externally in most species. The lip curls in as the 

 moUusk matures, forming a marginal channel which is filled with 



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