CAPSA. 



Capsa, as it now stands, is a small Genus of marine 

 shells, which are transverse, equivalve, inequilateral and 

 not gaping; in which particular they differ from the San- 

 guinolarise, but they resemble each other very nearly in 

 the teeth of the hing-e : in one valve there are two cardi- 

 nal teeth, diverging from a point close to the umbo, but 

 no lateral teeth, and in the other valve only one distinct, 

 bifid, cardinal tooth is to be seen, with two distant very 

 obsolete lateral teeth. The ligament is external, entirely 

 placed on the anterior side of the umbones. There is a 

 large sinus in the muscular impression of the mantle. 



The few species of this Genus known to us at present 

 are smooth shells, the C. brasiliensis, which we have re- 

 presented f. 1, is sometimes quite white, sometimes of a 

 ]>ale fulvous colour, but more frequently of a paler or 

 datker violaceous hue, and covered with an olive green 

 epidermis : the C. complanata is commonly of a yellowish 

 (;olour, and has a lighter ray beginning at the umbo and 

 iarreasing in width towards the edge of the shell; it has 

 u thin corneous epidermis. 



