124 UNIVALVES. 



PATELLA Grceca. 



CANCELLATED LIMPET. 



Specific Character. Shell ovate, thick, opaque, 

 strongly reticulated,* some of the longitudinal 

 ridges much coarser than the rest, and frequently 

 tuberculated by the crossing of the transverse 

 striae ; apex lateral, not much elevated, trun- 

 cated and furnished with an oblong perforation ; 

 colour pale, dull brown, or yellowish white ; 

 inside smooth, white, sometimes rayed with dull 

 red or brown ; margin crenated, sometimes in- 

 dented ; length about three quarters of an inch, 

 breadth scarcely half an inch, height a quarter. 

 It is rarely found on the British coasts of a 

 superior size ; some of the foreign specimens 

 are an inch long. This shell belongs to the 

 modern genus Fissurella. 



PATELLA Pellucida. 



BLUE-RAYED LIMPET. 



Specific Character. Shell sub-conical, thin, 

 pellucid, smooth; summit slightly recurved, 

 lateral ; of a dusky brown colour, rayed with 

 dotted lines of the brightest azure blue, lines 

 varying in number from three to seven ; length 

 nearly an inch, breadth not quite three-quarters. 



This species is common in many parts of the 



* Reticulated, crossed like net work, from the Latin, 

 reticul um 9 a small net. 



