UNIVALVES STROMBUS. 125 



STROMBUS Winged or Claw-Shell. 



DESCRIPTION OF PLATE XXV. 



Dnr. I. — Fig. 4. S. cliiragra. 

 Drv. ll.~-Fam. I. Fig. 2. S. polyfasciatus. 

 Fam. 1. Fig. 3. S. granulatus. 



Div. V Fam. 2. Fig. 5. S. paiustris. 



Div. VI. — Fig. 1. S. oniscus. 



Shell univalve, spiral; aperture much dilated; the lip expandiiuj, 

 and produced into a groove leaning to the left. 



THE distinguishing- character of this g-enus consists in 

 the position of its beak, which inclines to the left ; but 

 this distinction cannot always be relied upon, as the 

 younger shells are sometimes wholly destitute of any 

 beak, and hence a confusion with many other genera 

 has often taken place. 



The greater part of the shells which constitute the 

 first and second divisions, have their outer lip extended 

 either into the form of an expanded wing, (hence called 

 Alatae or Winged-shells), or projecting in distinct li- 

 near divisions or pointed claws ; but these appearances 

 are only manifest in adult shells. The most remarkable 

 of those species which have the lip terminated by claws 

 are the S. chiragra, S. scorpius, S. lambis and S. mille- 

 peda. The number of claws in the different species, 

 (with the exception of the S. pes-pelicani, which has 

 only four,) varies from six to ten. In some the claws 

 are nearly straight, and often smooth, while in others 

 they are very much curved, and covered with nodules. 

 The growth of these shells particularly deserves no- 

 tice: it has already been stated that the very voung 



