156 NEW- YORK FAUNA MOLLUSCA. 



GENUS CEMORIA. Leach. 



Shell small, cup-shaped. Apex elevated and curved forward, with a fissure just behind the 

 apex. 



Cemoria noachina. 



plate ix. fig. 195. 



Patella noachina. Lin. 



Cemoria ficmingii. Leach, Br. Shells, pi. 10, fig. 5. 



Rimula noachina. Couthouy, Bost. Journ. Nat. Hist. Vol. 2, p. 87. 



C. id. Gould, Invertebrata of Mass. p. 156, fig. 18. 



Discription. Shell small, conical. Apex recurved, obliquely perforated ; opening within 

 by a smaller aperture, which is covered by an arched scale. Surface covered with about 

 twenty unequal radiating ribs, which feebly crenate the margin of the aperture. Color, 

 bluish white. 



Length, 0'2. Height, 0"1. 



This remarkable little shell, which also occurs on the shores of Europe, has been only 

 obtained from the stomachs of fishes on our coast. 



(EXTRA-LIMITAL.) 



C. alternata? (Fissurella id. Say, Ac. Sc. Vol 2, p. 224.) Shell with equally concentric lines 

 crossed by alternately larger and smaller radii, all of which are not dilated : perforation oblique 

 oblong ; apex with an indented transverse line at the larger end of the perforation. Color, cinereous 

 or dusky; within white. Length, 0*8 - 1 - 5; diameter, 0'6 - 1 *0. Coast of the U. S, 



