486 Bulletin American Museum of Natural History. [Vol. XVI, 



Type, Nat. Mus. No. 21310, $ ad., skull, Bering Island, April 16, 1883; 

 Dr. L. Stejneger. 



Similar in general features to Phoca vitulina, but much larger, and 

 differing essentially in cranial and dental characters. 



Light Phase. Above deep straw yellow, profusely marked with very 

 small sharply denned black spots, most numerous on the back, from the 

 nose to the tail; ventral surface more sparsely spotted and general color 

 deeper yellow. Whiskers yellowish brown, perhaps from staining, flat- 

 tened, nodular for the basal half, the apical portion smooth, the longest 

 about 90-100 mm. in length. Nails brownish black, rather short and 

 stout. Those on the anterior digits range in length from 2 7 mm. on the 

 5th to 37 on the ist; on the posterior digits the nails are too imperfect 

 for measurement. The fore flippers are rather truncated, being less 

 pointed than in P. ochotensis, the end -of the 5th reaching to within 

 2530 mm. of the end of the ist, as against 50 mm. in P. ochotensis. 



Dark Phase. General ground color as in the light phase, but almost 

 obliterated by the profuseness of the dark spots, which occupy about 

 four fifths of the dorsal surface and rather more than one half of the 

 ventral surface. Over the median third of the dorsal region the spots 

 are more or less confluent, and are separated, when distinct, by very 

 narrow, irregular spots and bands of the ground color; on the sides and 

 below the spots are more separated and occupy only about one half of 

 the general surface. On the limbs the dark markings form large patches , 

 interspersed with much smaller areas of the ground color. Although the 

 dark specimen (No. 114652, Tchipunski Bay, southeastern coast of 

 Kamschatka) is a female, the difference is obviously not sexual, as one 

 of the light specimens is also a female. 



Young. A young specimen (No. if|jf!> Bering Island), about one 

 fourth grown (830 mm. long) , has the ground color lighter than in the 

 light phase of the adults above yellowish gray profusely spotted with 

 dusky, below pale yellow sparsely marked with dusky spots and blotches. 

 The dark markings are more or less veiled with the lighter ground color 

 and hence less sharply defined and grayish black rather than black, as in 

 the adults. This specimen, though only a few weeks old, is about the 

 size of a full-grown female Phoca hispida. The permanent dentition had 

 barely cut the gums. 



A fcetal specimen (No. 13990, $, Bering Island, March 12, 1883), 

 about 640 mm. long, has the general color pale yellow (white in life ?) , 

 with a narrow dorsal brownish band, darkest on the head, lower part of 

 back, and tail; upper surf ace of fore flippers dusky brown ; hind flippers 

 dusky grayish brown on both surfaces, less dark than upper surface of 

 fore flippers. 



External Measurements. The principal external measurements, taken 

 in the flesh by Dr. Stejneger, of four specimens killed on Bering Island 

 and neighboring points on the Kamschatkan coast, are as follows: 



