61 



Lucina squamosa 



Lucina sinuata 



lactea 



pecten 



• ••'•• undata 



lutea 



circinaria 



digitalis 



columbella 



globularis. 



DONAX. 



DONAX SCORTUM. LinnCBUS. 



Mawes Linn. f. 1 , pi. 9- 

 Shells of this genus are so singular in their form, that 

 they are immediately recognized ; they are transverse, 

 very inequilateral, almost triangular, a little flattened ; 

 the anterior side very much shortened, obtuse, and 

 appearing truncated, giving the shell the form of a 

 wedge; valves equal, a little gaping at. the front side, 

 and in many species dentated or finely crenulated on 

 the interior margin. Another very characteristic dis- 

 tinction of this genus is, its having at the hinge, besides 

 the primary teeth, one or two lateral teeth a little dis- 

 tant and separated from the cardinal ones, similar to 

 those of the Mactree, Lucinae, Tellinae, &c. In the 

 G, Venus, G. Cytheria, &c, the shortest side of the shell 

 is always the posterior, and the longest and largest hav- 



