50 SOLEN. 



The teeth, though differing in the species, are 

 very unUke those of tlie TelHnne, which most re- 

 semble some individuals of the genus in external 

 characters. 



Specimens of the oval and linear forms are pre- 

 sented in the plate j but they have not been divided 

 into sections, because there exist intermediate spe- 

 cies which it might be difficult to exclude from 

 either. 



The name Solen is derived from o-wAv-'j ^ title. 

 The Latin appellation Unguis, by which this family 

 has sometimes been designated, was probably given 

 on account of the nail-like or horny substance and 

 colour of many of the species. By the French 

 the shells have been called Manches de Gouteaux, 

 in allusion to their shape. 



