68 



** The plate of insertion of the hinder valve narroto, rather irregular. 

 t Margin hrisily ; lateral area distinct. 



A. nobilis, Gray. New Zealand. 



tt Margin spinose or spinulose ; lateral area indistinct. 



A. picea. Ch. piceus, Soįv. C. III. f. 147. "VVest Indies. 



A. spinigera. Ch. spinigerus, Sok\ Conch, III. f. 68. Peru. 



A. Owenii, Gray. West coast of Africa. 



A. spinosa. Ch. spinosus, Brug., Sow. C. Illust. f. 151. Australia. 



A. bre\'ispmosa. Ch. brevispinosus, Sow. C. Illust. f. 136. Island 

 of Johanna. 



A. magnifica. Ch. magnificus, Gray, Sow. C. Illust. f. 52. 



ttl" Margin smooth ? ; lateral area very distinct. 

 A. ? gigas. Ch. gigas, Gmel. Cape of Good Hope. 

 A. ? truncata. Philippines. 



4. SCHIZOCHITON. 



Valves elongate. subcordate, narrow ; lateral area short, distinctly 

 defined ; the hinder valves large, with a subposterior superior apex 

 and a deep notch on its hinder lower edges, and the plate of insertion 

 small, -vvith a few oblique notches, scarcely pectinated. Mantle 

 broad, covered above with smaU chaflF-like scales, deeply notched 

 behind. 



Schizochiton incisus. Chiton incisus, Soįv. Philippines. 



5. COREPHIUM. 



Valves broad ; \ving of insertion of the anterior valve lobed and 

 pectinated ; the hinder valve oblong, with a subcentral, subposterior, 

 not produced apex ; the edge of insertion distinct, not lobed on the 

 sides, \vith a single niek behind, and slightly denticulated ; mantle 

 spinose. 



C. echinatus. Chiton echinatus, Barnes. C. tuberculiferus, Sow. 

 Ch. spiniferus, Frembly, Sow. C. Illust. f. 47, young. 



6. Plaxiphora. 



P. Carmichaelis. Chiton Carmichaelis, Gray, Spic. Zool. Ch. 

 albidus, Blainv. 547. Ch. raripilosus, Blainv. 547. Ch. costatus, 

 Blainv. 547. Ch. biramosus, Quoy, Voy. Astrol. t. 74. f. 12, 16. 

 Ch. setiger, King, Z. J. v. 338 ; Sow. Conch. III. f. 17. Ch. Frem- 

 blii, Brod. P. Z. S. 1832, 28; Sow. Conch. III. f. 2. Ch. setosus, 

 Soto., Beechey Voy. Terra del Fuego. 



See also Ch. setosus, Sow. C. III. f. 19 ? 



7. Onithochiton. 



O. Gaimardi. Chiton Gaimardi, Blainv. 546. 



O. hirtosus. Chiton hirtosus, Blainv. 546. 



O. undulatus. Ch. undulatus. Van Diemen's Land. 



