284 MANUAL OF THE MOLLUSCGA. 
Synonyms, Schizo-chiton, Corephium, Plaxiphora, Onycho- 
chiton, Enoplo-chiton, Gray. 
Distribution, West Indies, Cape Horn, Falklands, Africa, 
Philippines, Australia, New Zealand, Valparaiso. 
Mopalia, Gray. C. Hindsii. Border hairy. 
Distribution, West America, Falkland Islands. 
Katharina, Gray. OC. tunicatus. Mantle covering all but 
the centre = the plates. 
Distribution, New Zealand, West America. 
Cryptochiton, Gray, ‘‘Saw-dust chiton.” C. amiculatus. 
Valves covered with scaly epidermis. 
Synonyms, Cryptoconchus, Sw. Amicula, Gray. 
Distribution, California, New Zealand. 
Acanthochites, Leach. (©. fascicularis. Pl. XI.. Fig. 30. 
Border ornamented with tufts of slender spines, opposite the 
plates. 
Distribution, Britain, Mediterranean, New Zealand. 
Chitonellus, Lam. O. fasciatus, Quoy. Pl. XI., Fig. 31. 
Border velvety ; exposed portion of the plates small, distant; 
apophyses close together. The dentition of chitonellus is repre- 
sented in Fig. 121. 
Distribution, 10 species. West Indies, West Africa, Philip- 
pines, Australia, Pacific, Panama. The chitonelle are found ir 
fissures of coral rock. (Cuming.) 
Fossil, Carb. Scotland. 
Gryphochiton, Gray. C. nervicanus. 
Helminthochiton, Salter, 1847. H. Griffithi, Salter, Geological 
VANE 121. Chitonellus. Tasmania. (Wilton.) 
LBA 
WK 
Journal. Plates sub-quadrate, not covered by the mantle: 
apophyses widely separated. 
Fossil, Silurian. Ireland. 
Brownia, Candei, D’Orbigny, 1853. A minute discoidal 
shell, associated with Helicophlegma in the first mstance, but 
distinguished by the serrated keels on its whorls, and lateral 
notches to the aperture. Cuba. 
Calcarella, spinosa, Souleyet, 1850. 
Shell sub- ‘globose, dextrally spiral, horny, pellucid, with three 
acutely serrated keels; aperture thickened, entire. Lateral 3 
