50 
SOLEN. 
The teeth, though differing in the species, are 
very unlike those of the Tellinse, 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 ; but they have not been divided 
into sections, because there exist intermediate 
species which it might be difficult to exclude 
from either. 
The name Solen is derived from <ru)Xriv, a tube, 
} 
The Latin appellation Unguis, by which this 
family has sometimes been designated, was pro- 
bably given on account of the w«i/-like or horny 
substance and colour of many of the species. By 
the French the shells have been called Manches de 
Couteaux, in allusion to their shape. 
