ISCHNOCHITON. 1^ 



Chiton clathratus REEVE, Conch. Icon., t. 18, f. 113, April, 1847. 

 Lepidopleurus pectinatus CPU., Proc. Califa. Acad. Nat. Sci. iii, p. 

 211, 1865; not L. pectinatus CPU. in Brit. Asso. Rep. 1863, p. 649, 

 (== I. cooperi CPU.), nor Chiton pectinatus SOWEKBY, also an Ischno- 

 chiton (ant., p. 64). Lepidopleurus pectinulatus CPR. MS., and of 

 American collectors and writers. 



Carpenter's diagnosis in Proc. Cal. Acad. Sci. seems to have 

 included both this species and I. cooperi, but he afterward distin- 

 guished them upon receipt of better material, and re-named the pres- 

 ent form " peqtinulatus" 



This species seems to replace I. mertensii south of Monterey. It 

 is a dingy, lusterless shell, resembling mertensii in the shape of the 

 girdle scales, which are, however, not so bright and clean in the 

 clathratus. It has decided riblets on the lateral areas, and the 

 lattice-work of the central areas is strong and much less finely cut 

 than in cooperi or mertensii. From I. cooperi, the different scaling 

 of the girdle, as well as the sculpture of the valves, separate this- 

 form. 



The second valve has divergent sculpture on the dorsal ridge, but 

 upon the other valves the riblets are parallel or nearly so there, and 

 the interstices are latticed. 



I. COREANICUS /Vdams & Reeve. PI. 27, fig. 50, (enlarged.) 



Shell ovate, rather elevated, terminal valves and lateral areas of 

 the rest radiately grooved, interstices convex, peculiarly grained, 

 grains prominent, round, solitary ; posterior terminal valve um- 

 bonated, extremity radiate, small, short ; central areas longitudinally 

 very finely granosely ridged, interstices between the ridges hollowed ; 

 lateral areas blackish-green, grains yellowish, central areas yellow- 

 ish blotched and variegated with black ; ligament finely granosely 

 coriaceous, tessellated dark and pale green. 



The sculpture of this species is not much unlike that of C. luridus ; 

 still it is distinct, and accompanied with a very characteristic style 

 of painting. The central areas of the shell are of a yellowish 

 ground, blotched and variegated with black. The terminal and 

 lateral areas are very dark green, with the prominent granules con- 

 spicuously tinged here and there with yellow. The ligament is 

 strikingly tessellated with dark and pale sea-green. (Eve.") 



Korean Archipelago, under stones (Belcher.)/ 

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