ISCHNOCHITON. 85 



deeply, coarsely grooved outside. Sinus with a somewhat concave 

 lamina, a trifle denticulate in some valves, and nicked at each side. 



Girdle gray, covered with convex, striated scales measuring '33 

 to '37 mill, in width (fig. 63). 



Length 25 mill. ; divergence about 95. 



China Seas or Japan. 



The type is a well-grown specimen, evidently adult, and complete 

 except that valve vii has been lost. Valves i, vi and viii are 

 detached, and the last has lost its sculpture posteriorly from an ill- 

 judged cleaning with some sharp instrument. The remaining valves 

 and the girdle are perfect. 



This is a well-characterized species, being separated from other 

 allied Lepidozonas by the more numerous radii of lateral areas and 

 end valves. It must, however, be carefully compared with 1. corea- 

 nicusA. & R. (Vol. XIV, p. 129), which is prior in date, and which 

 I suspect may prove the same, although I have not seen an 

 authentic specimen. Reeve's figure of coreanicus is said by him to 

 be enlarged, but the actual size is not stated. 



I. LUZONICUS Sowerby. Vol. XIV, pi. 38, figs. 31, 32 (enlarged). 



Shell oval, angulate, straw-colored with longitudinal streaks of 

 green ; lateral areas and end valves radially granulated ; central 

 areas acutely longitudinally sulcate ; margin nearly smooth. 



Length 9, breadth 5 mill. (Sowb.') 



Luzon, Philippines, on dead shells in 15 fms. 



Chiton luzonicus G. B. SOWERBY, JR., P. Z. S. 1841, p. 104 

 REEVE, Conch. Icon., t. 25, f. 167. 



Carpenter's remarks upon the type specimens are as follows : 6 

 specimens, Mus. Cuming. In very poor condition ; must have lost 

 the girdle scales, and faded in color. Looks extremely close to the 

 young of coreanicus, which I think it is. The lateral areas have 5 

 or 6 close granular ribs; central areas having 11 sharp, distinct 

 riblets on each side ; the riblets are granulose and are a little decus- 

 sated between ; jugum sharp. Girdle has very few scales to be seen, 

 but these seem to be like Lepidopleurus, not very large but round- 

 ish. Another specimen has about 17 very close moniliform riblets 

 on the central areas, the side areas raised but ribbed only very indis- 

 tinctly, with scattered grains on them. The scales of this shell are 

 very much smaller, and Ischnoid, striated, flat. 



