38 CONCHOLOGY. 



callosity; two muscular impressions. Inhabits the Mediterranean 

 sea. One species. 



Panopaea aldrovandi. 



3. Genus Solectirtus. PI. VI. 

 Animal. Unknown. 



Shell. Oval, elongated, equivalve, subequilateral, with edges 

 nearly straight and parallel, the extremities equally rounded, and, 

 as it were, truncated ; summits but little marked ; hinge without 

 teeth, or formed by some rudimentary primary teeth, ligament 

 projecting, affixed to thickened callosities ; two distinct rounded 

 muscular impressions. Mediterranean sea. Three species. 

 Solecurtus radiatus. Solecurtus strigilatus» 



S. legumen. 



4. Genus Glycimeris. PI. VI. 

 Animal. Unknown. 



Shell. Covered with epidermis, slightly irregular, elongated, 

 gaping at both ends, equivalve, exceedingly inequilateral ; sum- 

 mits little marked ; hinge toothless ; a longitudinal callosity. 

 Ligament exterior, affixed to very projecting callosites on the 

 shortest side of the shell; two distinct muscular impressions. 

 Inhabits the north seas. Two species. 



Glycimeris margaritacea. Glycimeris siliqua. 



FAMILY IV. 

 Mtaria. Two genera. 

 1. Genus My a. PI. VI. 

 Animal. Subcylindrical, enveloped in a mantle pierced only 

 with one interior and inferior hole for the passage of a very 

 small and conical foot ; the tubes very considerable, and com- 

 pletely united ; a tolerably large mouth, oval, and with simple 

 lips ; very small labial appendages ; branchial laminae inconsider- 

 able ; the external very short, the internal united with that of the 

 opposite side. 



Shell. Surrounded with a thick epidermis, which is prolonged 

 upon the tubes and the edges of the mantle of the animal : tolera- 



