PIERCED SHELLS AND CHITONS 



247 



arched. Externally the shell is reddish, while the 

 inside is smooth and silvery, without visible muscle- 

 scar. The shell is tolerably thick, and appears very 

 compact and solid. 



Quite in contrast with this species is the next, 

 Haliotis cjigantea^ Chem., the Japanese Abalone, 

 which seems to have followed the warm ocean cur- 

 rent down past the Aleutian Islands, and to have 

 reached the central part of the California coast; 

 but it became smaller as it progressed, so that here 

 it does not deserve its original name, though there 

 seems to be no sufficient reason for separating it, 

 even as a variety. My best specimens came from 

 the west coast of Vancouver Island, the largest meas- 

 uring five inches in length. In shape it appears long 

 and narrow when compared with other species. The 

 shell is thin, the edge sharp, the spire quite prom- 

 inent, the surface uneven, while the four open holes 

 are large and surrounded by high walls. The in- 

 terior is very iridescent, a 

 light color prevailing, and 

 the muscle-scar is not dis- 

 tinct. 



After the shells that 

 have several holes, which 

 we have just considered, 

 there come a number hav- 

 ing only one opening, 

 which answers the same 

 purpose, that of allowing 

 a free outward passage 

 from the interior of the Fig. 246(*) 



