OALYPTR^ID^. 213 



Animal. Head large, transverse, depressed ; foot rounded, 

 slightly truncate in front. 



Adhering to shells or stones, and modifying their form in 

 accordance with their dwelling-place, those species living within 

 the aperture of empt}^ spiral shells are generally flat and uncolored ; 

 others reproduce the ribs of Pecten ; others again attach in 

 groups upon the outside of each other's shells. 



GARNOTiA, Gray. Oval, convex, covered by a smooth epider- 

 mis ; apex dorsal, median, posterior; lamina inclined. 



lANACus, Morch. Shell depressed, apex posterior, but slightly 

 lateral ; lamina mostly concave in front. G. u7iguiformis, Lam. 

 (Ixv, 92;. 



ERG^A, H. and A. Adams. Shell depressed, summit lateral; 

 lamina produced in front, its columellar margin subtubular. C. 

 plana^ Ads. and Rve. (Ixv, 93). 



NOiciA, Gray. Shell subcircular or oblong, convex, spiral ; 

 whorls one and a half or two ; the apex subcentral, subposterior; 

 nucleus spiral ; cavity concave, deeper under the apex ; internal 

 plate concave, thin, with the fold forming a narrow linear cavity 

 open to the apex of the shell. N. Chinensiii, Gra3^ China. 



SPiROCRYPTA, Gabb. Summit of shell posterior, lateral and 

 submarginal, spiral. Internal plate attached to the margin on 

 the lower or outer side, curving upwards and inwards and 

 uniting with the opposite side at a considerable distance. The 

 plate is subspiral, thus approaching Trochita and Galerus. C. 

 p^7e^^7}^, Gabb (Ixiv, 18). Cretaceous; Cal. 



Galertculus, Seeley. 



Di^tr.— G, alius, Seeley (Ixiv, 79). 



This genus has two separate septa, the larger one originating 

 below the incurved apex, and the smaller one at the base. Only 

 the cast is as yet known ; the upper surface of the shell, which 

 has the form of a Helcion, not having been observed. 



Capulus, Montf. 



Bonnet-limpet. 



Syn. — Pileopsis, Lam. Actita, Fischer de Wald. 



Distr. — 8 sp. W. Indies, Europe, India, Australia, W. America. 

 Fossil, 20 sp. Silurian — . G. Unga7'icus, Linn. (Ixvi, 30). 



Shell conical, apex posterior, spirally recurved ; aperture 

 rounded ; muscular impression horseshoe-shaped. 



Tongue-membrane winged on each side in front, teeth arranged 

 in seven series (o-l"3), central teeth small and iDroad with the 

 apex hooked, the lateral teeth long and hamate. Rostrum 

 lengthened ; tentacles subulate, with the eyes on bulgings at 

 their outer bases. Mantle simple in front ; gill forming a single 

 plume placed obliquely across the mantle-cavit}^, laminae elongate, 

 linear, partly exposed. Foot folded on itself, the sides simple, 



