152 MANUAL OF THE MOLLUSCA. 



Animal with a broad muzzle ; tentacles rather short ; lanceolate ; eyes on 

 bulgings at the outer bases of the tentacles; mantle-margin simple, sides 

 plain. Found under stones, between tide-marks, and in shallow water 

 (Cuming). 



Distr., 50 sp. W. Indies, Honduras, Brit., Medit., Africa, India, Philip- 

 pines, China, Japan, New Zealand, Gallapagos, Chili, 



Fossil, 30 sp. Garb ? chalk. Brit., France, &c. 



, Sub-genera. Crucibulum, Schum. (Dispotaea, Say., Calypeopsis, Less.) 

 Ex. C. rudis, PL XL, fig. 12. Shell spinulose ; internal cup entire ; attached 

 by one of its sides. Distr., W. America, Japan, W. Indies. Found on shells, 

 with its base worn, or smoothed by a shelly deposit (Gray). Between this 

 section and the next there are several intermediate forms. 



Trochita, Schum. (Infundibulum, J. Sby., Galerus, Humph. Trocha- 

 tella and Siphopatella, Lesson.) T. radians, PI. XL, figs. 13, 14. (=Patella 

 trochoides, Dillw.) T. sinensis, PI. XL, fig. 15. Shell circular, more or less 

 distinctly spiral ; apex central ; interior with a more or less complete sub- 

 spiral partition. Distr., chiefly tropical, but ranges from Britain to New 

 Zealand. T. prisca (McCoy) is found in the carb. limestone in Ireland ; and 

 several large species occur in the London clay and Paris basin. The recent 

 C. sinensis the " China-man's hat" of collectors is found on the southern 

 shores of England, and in the Mediterranean, in 5 10 fins, water (Forbes). 

 Its lingual dentition is given by Loven ; median teeth broad, hooked, den- 

 ticulated ; uncini 3, the first hooked and serrated, 2, 3 claw-shaped, simple. 

 CREPIDULA, Lam. 



Etym., crepidula, a small sandal. 



Type, C. fornicata, PL XL, fig. 16. Syn., crypta, Humph. 



Shell oval, limpet-like ; with a posterior, oblique marginal apex ; interior 

 polished, with a shelly partition covering its posterior half. 



The crepidulse resemble the fresh -water navicellae in form ; but the inter- 

 nal ledge which mimics the columella of the nerite, is here the basis of the 

 adductor muscles. 



They are sedentary on stones and shells, in shallow water, and are some- 

 times found adhering to one another in groups of many successive generations. 

 The specimens or species which live inside empty spiral shells are very thin, 

 nearly flat, and colourless. 



Distr., 40 sp. W. Indies, Honduras, Medit., W. Africa, Cape, 

 Australia, W. America. 



Fossil, 14 sp. Eocene . France, N. America, Patagonia. 

 PILEOPSIS, Lam. Bonnet-limpet. 



Etym., pileos, a cap, and opsis, like. 



Syn., capulus, Montf. Bronchia, Bronn. 



Type, P. hungaricus, P!. XL, fig. 1?. P. militaris, PL XL, fig. 18. 



