UNIVALVES. STROMBUS. 103 



STROMBUS. WINGED OR CLAW-SHELL. 



Animal a Limax; Shell univalve, spiral; aperture much 

 dilated; the lip expanding, and produced into a groove 

 leaning to the left. 



THE distinguishing character of this genus, of which 

 there are forty-six species, consists in the position of its 

 beak, which inclines to the left; but as the younger shells 

 are sometimes wholly destitute of any beak, a confusion 

 with many other genera is often difficult to be avoided. 



The Strombi seem to have a propensity to extend their 

 outer lip, either into the form of an expanded wing, hence 

 called alatse or winged shells, or to continue it into long 

 and pointed claws: but these appearances are only mani- 

 fest in adult shells. 



The most prominent species of the division which has the 

 lips terminated by claws, are the following : S. chiragra, 

 S. scorpius, S. lambis, and S. millepeda. The number of 

 claws in the different species varies from six to ten, but 

 the S. pes-peticani has only four. In some species they 

 are nearly straight, and often smooth, while in others they 

 are very much curved, and covered with waved nodules. 

 The growth of these shells is worthy of notice. It has al- 

 ready been stated, that the very young shells have no ap- 

 pearance of claws, which first shew themselves in the form 

 of short and open spouts; when the shells are farther ad- 

 vanced in growth, they assume the shape they are to retain, 

 but are still thin, hollow, and imperfectly closed ; and it is 

 only in the adults that they become solid, and have a thick, 

 strong, and horn-like appearance. 



The S. oniscus, in the sixth division, is totally destitute 

 of a winged termination; and the S. fasciattis, S. pugilis, 



