260 WEST COAST SHELLS 



from the apex of each valve. The girdle is generally 

 quite rough, but sometimes we find it nearly smooth. 

 This species ranges from ^'ancouver Island to Mon- 

 terey. It should be remarked that specimens have 

 been found connecting this species with the last two, 

 so that by Pilsbry it is considered to be only a sub- 

 species. The difficulty of drawing hard and fast 

 lines will be appreciated by any one who makes a 

 study of this group. 



Mopalia ciliata, Sby., the Hairy Chiton, has also 

 been sadly confused with other species. It is brighter 

 colored than M. muscosa. The girdle is wide, yellow 

 or brown, somewhat clothed with curling, strap-like 

 brown hairs, which bear near their bases a bunch of 

 minute, white, acute spines. It extends along the 

 coast from the far north to Monterey. The variety 

 wosnessenskii^ Midd., has a shell elongated, the back 

 roundly arched, olive to drab in color, and with faint 

 sculpture. It has been found at Sitka and Olympia. 



From those which it is difficult to 

 classify we pleasantly turn to a very 

 distinct species, Placiphorella vela- 

 tcU Cpr., the Veiled Chiton, shown 

 in Figure 258. This singular spe- 

 cies is more nearly circular than any 

 of its relatives on this coast. At the 

 anterior end the mantle projects con- 

 siderably, forming a distinct veil, 

 which is set with scattering hairs. The valves are low 

 arched, of a dull reddish color without, but whitish 

 within. Its length is 30 to 50 mm., and it is found 

 from Humboldt Bay southward. 



