12 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54. 



Length of entire animal (type-specimen) 24, of shell 22 mm.; 

 width of same 13, of shell 9 mm.; maximum width of girdle, 2.7 mm. 



Type.— Cat. No. 215632, U.S.N.M. [S. S. B. 118]. 



Type-locality. — Station 4810; 195 fathoms; bottom of fine gray- 

 sand; bottom temperature 44.7° F.; off Cape Sirakami, Japan; July 

 16, 1906 (two specimens). 



Remarks. — This handsome species is well characterized, the only 

 one apparently requirmg comparison with it being the /. craticulatus 

 of Gould, but the latter is a more heavily granulose species and 

 should be, according to the figures given by Pilsbry in his Manual, 

 quite easy to distinguish. The special features of /. pilshryanus 

 seem to be in brief as follows: 



1, the pale, tawny coloration. 



2, the sharply arched, elevated shell. 



3, the sculpture of numerous finely granulose rib lets prevailing 

 nearly all over the shell, and the arrangement of the pustules in 

 squares without interlatticing on the central areas. 



4, the reduplication of teeth and slits in many of the intermediate 

 valves. 



5, the numerous insertion slits (13) in each of the terminal valves. 



6, the crowded, closely imbricating, v.ery finely ribbed-striate 

 dorsal scales. 



The dedication of this species to Dr. Henry A. Pilsbry will require 

 no apology to students of the group. 



Family MOPALIIDAE. 



Genus PLACIPHORELLA Carpenter, 1878. 



PLACIPHORELLA STIMPSONI (Gould, 1859). 



Plate 8, figs. 1-2; plate 9. 



1859. Chiton {Molpalia) stimpsoni Gould, Proc. Bost. Soc. Nat. Hist., vol. 7, 



p. 161. 



1860. Chiton {Molpalia) stimpsoni Gould, Otia Condi., p. 118, [fide Dall]. 

 1886. Placiphorclla stimpsoni Dall (part), Proc. U. S. Nat. Mus., vol. 9, p. 210. 

 1892. Pladphorella stimpsonii Pilsbry, Man. Conch. (1), vol. 14, p. 307, pi. 62, 



figs. 84-87. 



Material. — The Albatross expedition took two specimens of this 

 species between tides at Hakodate, Japan [S. S. B. 93]. 



Remarks. — I can add little to the excellent description given of 

 the apparently somewhat variable shell characters by Pilsbry, but 

 the preservation of the specimens in alcohol renders possible a few 

 additional observations on the girdle. There is a series of large 

 bristles near the middle of the girdle, one opposite each suture, and 

 five or six continuing around the head valve. Other series of large 

 bristles adorn the anterior lobe, more especially near the margin, in 



