V'OL. VII] 



BERRY— WEST AMERICAN CHITONS 



243 



Type: A specimen in alcohol [S. S. B. 240] entered as Cat. 

 No. 1411 of the author's collection. Paratypes have been de- 

 posited in the collection of the California Academy of Sciences 

 and the private collection of Mr. George Willett. 



Fig. 3. Placipliorella rufa Berry, camera outline of dorsal 

 aspect of type specimen, x2i/2. 



Type Locality: 15-25 fathoms, Forrester Island, Alaska; 

 George Willett, July, 1914-1916; 15 specimens. 



Remarks: The fine series of specimens obtained by Mr. Wil- 

 lett shows that P. rufa is a very distinct species, standing quite 



Fig. 4. Placipliorella rufa Berry, camera outline of dorsal 



aspect of a juvenal from Forrester Island, 



Alaska [S. S. B. 242a], xV/z. 



alone with respect to certain of its characters, but on the whole 

 undoubtedly nearest to the members of the P. vclata group of 

 the genus. From P. velata and its analogue P. stiinpsoni, our 

 form is readily distinguishable by its warm, ruddy external 



