118 ISCHNOCI1ITON. 



front; lateral areas elevated, sculptured with 6 radiating sulci ; 

 central areas irabricately sulcate. Girdle narrow, banded with 

 olivaceous, covered with minute scales. 



Length 13, breadth 9 mill. (Old.) 



Interior: terminal valves with about 14, central valves 1 slit; 

 teeth very acute, but a little serrated at the edge. Eaves large ; 

 sinus narrow, vaulted, scarcely laminate. Girdle irregularly 

 imbricated with transverse, solid, neatly smooth scales. (Cpr.) 



China Sea, Lat. 24 N. 



Chiton (Lepidopleura) lepidns GLD., Proc. Bost. Soc. N. H. vii, p. 

 164 ; Otia, p. 118. Ischnochiton lepidus CPR., MS. 



The girdle scales are those of Lepidopleurus, [==zLepidozona~\ 

 except that the imbrication is irregular. The species is remarkable 

 for the narrow, arched sinus; and for the slight serration of the 

 insertion plates which are yet normally sharp and protected with 

 broad eaves. I have not been able to re-examine the type since I 

 matured a plan of arrangement for the sections of the genus. ( Cpr.) 



I. PETALOIDES Gould. PI. 23, figs. 92, 93. 



Shell small, delicate, elliptical, roundly arched, very slightly car- 

 inated, the valves not beaked, of a pale lemon-yellow ground color, 

 reticulated along the centre, with delicate, angulated, pale-violet 

 lines ; these areas are also rugosely lineate-punctate longitu- 

 dinally, especially toward the margin ; lateral areas very prominent, 

 rugosely granulate, and with about four, fine radiating stria3 ; pos- 

 terior valve acutely umbonated and crossed by an acute, transverse 

 rib. Margin cream-colored, very finely gran ulate-i rubricate. 



Interior : posterior valve having 9, central 1, ant. v. 9 slits ; teeth 

 acute ; eaves acute, hardly spongy ; sinus very wide, short, smooth. 

 Girdle imbricated with flat, scarcely striated scales. (Cpr.~) 



Length 12J, breadth 10 mill. 



Kauai and Oahu, Sandwich I*. 



C. petaloides GLD., Proc. Bost. Soc. N. H. ii, p. 144, July, 1846 ; 

 U. S. Expl. Exped., Moll. Sh., p. 328, f. 435 ; Otia Conchol., p. 6 ; 

 C. (Lucia) petaloides GLD., Otia p. 242. Lophyr as petaloides PSE., 

 Amer. Journ. of Conch, vii, p. 194. Ischnochiton i>d1oides CPR. 

 MS. 



The scales are rather large for the size of the shell, but thin. 

 Fresh specimens have sometimes an appearance of minute striula- 



