Genus 3. 

 TELLINA. 



GENERIC CHARACTER. 



Animal Tethys. 



Testa bivalvis, anterius hinc ad alterum latus flexa. 



Cardinis dentes (utplurimum) tres; laterales plani alterius testa?. 



Animal a Tethys. 



Shell bivalve, the anterior part curved to one side. 



Hinge usually with three teeth ; lateral teeth, in one of the valves, flat. 



GENERAL OBSERVATIONS. 



The shells of this genus are, with one or two excep- 

 tions, of equal valves. That part of the Linnaean de- 

 finition, which relates to the anterior part being curved 

 to one side, must be taken with some limitation, since, 

 in many species of the genus, this flexure is not visible; 

 but the striae, where this is wanting, are generally seen 

 to diverge on the same part of the shell. Several of the 

 species are deficient in lateral teeth. 



There is so little apparent difference between some of 

 the Tellens, and shells of other genera, especially those 

 of Solen, and Venus, that it is sometimes difficult to de- 

 cide to what particular genus they properly belong. This 

 similitude was the cause of great confusion among both 

 ancient and modern conchologists, till Linnaeus affixed 

 his scientific characters to the genus, and determined 

 the species. Still, however, in the opinion of the French, 

 there is room for improvement, since from the Linnsean 



