51 



TEL LIN A. 



A. Ovate and thickish. (Plate V. Fig. 2.) 



B. Ovate compressed. (Fig. 3.) 



C. Suborbicular. (Fig. 4.) 



Shell compressed towards the anterior slope, and 

 often bent. Teeth of the hinge mostly three ; 

 lateral teeth plain, or not existing, in one of the 

 valves. (Fig. 1.) 



The beaks are very short, and usually lean to- 

 wards the ligament, which is large, and covers the 

 prominent margin of the suture. 



It is difficult to beginners in the science of Con- 

 chology to discriminate between the genera Tel- 

 lina and Venus. In the forms of the shells, one 

 genus much resembles the other ; and the teeth 

 of some small species are not distinct to an inex- 

 perienced eye. The difference will therefore best 

 be learnt by observing principally the inclination 

 of the beaks : if they at all tend towards the liga- 

 ment, the shell will belong to the genus Tellina ; 

 also, if any remote lateral teeth be discernible, 



