CHITON* 17 



many of the corresponding ridges are also sulcated at 

 the end : the middle valves are grooved in the same 

 manner, and most of the marginal triangles are formed 

 of three deep unequal furrows. The specimen from 

 which our figure Was taken, has but few scales remaining, 

 but the impression of the rest is plainly visible. The 

 colour sordid brown, inclining to black on the back 

 part of the middle valves ; inside greenish white ; length, 

 when extended, four inches ; breadth, an inch and a half, 

 This rugged shell is said to inhabit the South seas. 



BICOLORED CHITON. 



21. Chiton bicolor. Ch. testa octovalvi crassa dorsataj extus thdiassinai 

 . intusnivea.,margine nigra. Linn. Gmel. p. 3204. 



Shell of eight valves, thick and ridged ; outside sea-green ; inside snow- 

 white, edged with black. 

 Chem. Conch. 8. t. 94. f. 794, 795. 



The middle valves in this shell bend slightly upwards, 

 the marginal triangles striated, the anterior valve marked 

 with radiate striae. 



We have the authority of Chemnitz only for this 

 species, who figured it from a specimen in his own 

 cabinet. The uniform sea-green colour is a distinguish- 

 ing characteristic. It is about two inches and a quarter 

 long ; its country unknown. 



CHERRY CHITON. 



22. Chiton cerasinus. Ch. testa octovalvi cerasina Icevi; marginis 

 dentibus niveis. Linn. Gmel. p. 3204. 



Shell of eight cherry-coloured valves, smooth ; marginal teeth snow- 

 white. 

 Chem. Conch. 8. t. 94. f. 796. 



The shell is oval, about an inch and a half long, and 

 of a dark cherry colour. Country unknown. 

 vol. i. c 



