74 



CONCHOLOGY. 



Fifty-nine species — and, 

 fossil. 



Pecten maximus. 



P. Jacobseus. 



P. bifrons. 



P. zigzag. 



P. medius. 



P. Latirentii. 



P. pleuronectes. 



P. purpuratus. 



P. pallius, 



P. imbricatus. 



P. asperimus. 



P. varius. 



P. glaber. 



P. grisens. 



P. liabellatus. 



P. quadradiatus. 



P. Tranquebaricus 



P. liybridus. 



P. obliteratus. 



P. Magellanicus. 



P. iineolaris. 



P. nodosus. 



P. pusio. 



P. gibbus. 



P. ornatus. 



P. florens. 



P. opercularis. 



P. tigris. 



P. histrionicus. 



according to Defrance, ninety-eight 



Pecten turgidus. 

 P. aspersus, 

 P. plicus. 

 P. rastellus. 

 P. flagellasus. 

 P. flavidulus. 

 P. Japanicus. 

 P. radulus. 

 P. pes-felis. 

 P. sauciatus. 

 P. aurantius. 

 P. sinuosus. 

 P. virgo. 

 P. Isabella. 

 ' P. flexuosa. 

 P. inflexus. 

 P. miniaceus. 

 P. lividus. 

 P. sulcatus. 

 P. unicolor. 

 P. distans. 

 P. irradians. 

 P. dispar. 

 P. Islandicus. 

 P. sulphureus. 

 P. pellucidus. 

 P. sanguineous. 

 P. senatorius. 

 P. lunatus. 

 P. lineatus. 



4. Genus Plagiostoma. 



Animal. Entirely unknown. 



Shell Moderately thick, regular, free, subequivalve, sub- 

 auriculated, the two valves nearly equally dilated, both provided 

 with a distinct summit reflexed to the middle of a plane surface, 



