276 HALIOTID.E. 



Lamarck, C. succinea, Risso, C.Polii, Sc&cchijC. vulgaris } 

 Philippic and C. mamma, Krynicki fide Middendorff. 



Crepidula sinuosa of Turton was included by him in 

 the catalogue of British shells, in consequence of Mr. 

 Bean having taken specimens at Scarborough, " from 

 the bottom of a ship just arrived from North America." 

 It is the C. plana of Say ; but I question its being iden- 

 tical with the Patella crepidula of Linne or C. ungui- 

 formis of Lamarck, as was supposed by Sowerby and 

 Gould. 



Family V. HALIO'TIDiE, Fleming. 



Body oblong, depressed, partly spiral : mantle puckered in 

 small folds at intervals on the right hand : head broad, with 

 a short snout : tentacles filiform, long and tapering, separated 

 by a fringed lobe or membrane, which forms a head-veil : eyes 

 placed on cylindrical, but short, stalks at the outer bases of the 

 tentacles : gills two, unequal in size : foot extremely large, 

 thick and fleshy, encircled by a double row of festoons. 



Shell ear-shaped, nacreous, pierced on the right side by 

 a series of holes, which are closed in the course of growth, 

 after ceasing to be of use in containing the pallial folds ; the 

 hole last formed commences as an open notch : spire very short, 

 placed on the left side, although almost terminal : mouth ex- 

 tremely large and open, occupying nearly the whole of the 

 base ; borders curved, that on the right being thick, and 

 the other thin : inside highly iridescent. 



This family has several points of relationship to the 

 Fissurellidce ; but the shape is different, the orifices are 

 numerous, and the shell is remarkably nacreous. There 

 appears to be a homogeneity between all the genera or 

 members of the Haliotidce, making it difficult to dis- 

 tinguish one from another. We have only the typical 

 genus. 



