GASTEROPODA. 



121 



are often of a very irregular outline at the circumference ; 

 like the Patella, they constantly remain upon the same 

 portion of rock, and form the margin to agree with its 

 shape. They are found in great abundance at the Cape 

 of Good Hope and California. One species frequently 

 fixes itself upon other living shells, particularly upon the 

 Purpura, and of course follows it in all its movements. 



Capulus. Montf. (Pileopsis Lam. ; Amalthea Schum. ; 

 Actita Fisch. ; Acroculia Phil.) — 

 Shell irregular, conical, dilated at 

 the aperture ; the apex lengthened, 

 and spirally recurved backwards; 

 inside dull, but having a horse-shoe 

 shaped impression ; aperture large ; 

 epidermis very soft, like velvet. 

 Animal, with a head produced into a proboscidiform 

 muzzle ; tentacula two, long, subulate, unconnected, with 

 the eyes on bulgings at their external bases ; mantle 

 fringed at the margin ; branchial plume single ; foot 

 strong, suborbicular, its sides plain ; tongue rather long, 

 with a cordate membranous border at its anterior ex- 

 tremity ; lingual teeth arranged in transverse series of 

 seven, of which the central one is small and broad, with a 

 hooked apex, and the others long and hamate.* 7 species ; 

 also fossil. 



These shells are frequently called, from their shape, the 

 Fool's Cap Limpet. They are found in the European Seas 

 principally : but some very large species are inhabitants 

 of tropical climates, and are met with in the Pacific Ocean, 

 and in the East and West Indies, Mediterranean, Australia, 

 and California. The shells of this genus, like many of the 

 species of Patella, are supposed to remain constantly attached 



* Forbes's British Moll. 



