133 



PATELLA lata. 

 TAB. CCCCLXXXIV.— /g^. L 



Spec. Char. Obovate^ depressed, nearly smooth, 

 radiated ; radii about 30, distant, rounded ; 

 apex very excentric. 



Not much longer than wide, very shallow, and rather 

 irregular ; the apex is placed at about one third the 

 length of the base from the anterior edge. The radii 

 are strongest and most distant upon the posterior por- 

 tion. 



This is probably one of the rarest productions of the 

 Stonesfield slate : it was lately in the possession of Mr. 

 G. Humphries. The portion that is broken off from the 

 upper part, discloses something within that has the ap- 

 pearance of a section of the cup-like appendage of a Ca- 

 lyptraBa; but as the apex is regular and not oblique, and 

 this appearance is very imperfect, it does not seem suf- 

 ficient evidence of its not being a Patella : it would be 

 fortunate to find a specimen showing the under surface, 

 but in this the shell adheres too closely to the stone to 

 allow any hopes of being able to remove it. A view of 

 the muscular impression would decide it to be a Patella. 



