I'.t 



The valve- an- wholly eoneealrd, white or lle>h-eolored. entirely 

 lacking the outer colored layer (tegmentnm i of ot her ( 'hitoiis ; their 



are more or less thinned and ereniihited by radial M 

 Anterior valve (figs. 8, 9) having the apex ut the posterior third, 

 and with 4 to 7 slits. Intermediate valves (firs. P-', l-'J; having the 

 apex near the posterior third ; formed of two large anterior lobes 

 expanded at the sides, and two smaller, narrow posterior lobes. 

 Posterior valve (figs. 10, 11) having the mucro posterior or near the 

 posterior third ; deeply sinused in the rear, and usually having a 

 slit on each side of the sinus. 



Girdle leathery, thick, red, densely covered with countless minute 

 fascicles of vermilion spinelets (pi. 6, fig. 6.) 



Length 15 to over 20 cm. 



I-^idrnno Harbor, south of Jesso, Japan] Sakalin Island; Kuril 

 Is. ; southern extremity of Kamchatka ; Aleutian Is. ; Alaska and the 

 whole American coast southward to Monterey and the Santa Barbara 

 Is.; just below tide mark. 



Chiton stelleri MIDD., Bull. Acad. Sci. St. Petersb. vi, p. 116 

 (1846). Chiton ( Cryptochitoii) stelleri MIDD., Mai. Ross, i, p. 93, 

 t. 1-9 ; Mem. de TAcad. Imp. Sci. St. Pe*tersb., 6me Ser., vi, p. 101, 

 157, 1849 (full account of anatomy). SCHRENCK, Amurl. Moll., 

 p. 271 Cryptochiton stelleri GRAY, Guide Syst. Dist. Moll. B. M., 

 p. 185 (1857). H. & A. AD., Gen. Rec. Moll, i, p. 479 ; iii, t. 55, 

 f. 1. CPR., Suppl. Rep., etc., Brit. Asso. 1863, p. 648. GABB., 

 Palaeontol. Cal. ii, p. 87. DKR., Ind. Moll. Mar. Jap., p. 159. 

 SMITH, Ann. Mag. N. H. 1875, xvi, p. 115. DALL, Proc. U. S. Nat. 

 Mus. 1878, p. 311; p. 299, t. v, f. 44 (dentition). Cryptochiton 

 stelleri var. violacea NORDMANN, Bull. Soc. Imp. des Naturalistes de 

 Moscou, xxxv, 1862, p. 329, t. iv. Chiton amiculatus Sow B., Conch. 

 Illustr., f. 80, SObis., and GRAY, P. Z. S. 1847, pp. 65, 69, 169. NOT 

 of Pallas. Chiton sitkensis REEVE, Conch. Icon., Chiton, t. 10, f. 

 55; t. 11, f. 55b (1847); not C. sitkensis Midd. Chiton chlamii* 

 REEVE, I. c., t. 11, f. 60. Chiton californicus PRESCOTT, Amer. 

 Journ. Sci. and Arts (2), xxxviii, p. 185, fig. in text. (Sept., 1864). 

 ? ? Chiton giganteiis Kamtschaticu* TILESIUS, Mem. de 1 'Acad. St. 

 Pi'tersb. ix, 1824, p. 473, t. 16, f. 1, 2 ; t. 17, f. 3-8 (in part). 

 Cryptochiton amus in the Dorpat Collection, testeMidd., Mai. Ross 

 i, p. 40. 



The foot and softer parts of this species are eaten raw by the 

 Aleuts and Indians. 

 4 



