4 THE FUE SEALS OP THE PRIBILOF ISLANDS. 



But with the head it should be different. If we take out the measurements whioh 

 have to do with this feature we find that there is a marked difference correspoadiag 

 to the general impression made by comparative observations on the two herds. These 

 measurements reduced to percentage of the total length are as follows, the results 

 being all the more striking because in each case the Pribilof animal shows a smaller 

 total length : 



Miasurements (in millimeiers), showing differences in the head of typical Commander and Pribilof seals, taken 



from the table just given. 



Total length 



Distance between eyes. 

 Per cent of total length. 

 Distance between ears. . 

 Per cent In total length 

 Distance nose to eye — 

 Per cent in total length. 

 Distance nose to ear . . . 

 Per cent in total length 



Adult male. 



Com- 

 mander. 



1,930 

 104 



5.3 

 170 

 9.1 

 98 

 S 

 213 

 11 



Pribilof. 



1,887 

 127 



6.7 

 306 

 16.2 

 115 

 G 

 216 

 11.4 



Adult female. 



Com- 

 mander. 



70 

 5.4 

 138 

 10.7 

 67 

 5.2 

 168 

 13.1 



Pribilof. 



1,262 



89 



7 



204 



16.1 



89 



7 



181 



14.3 



Bacheior. 



Com- 

 mander. 



1,285 

 71 

 5.5 

 138 

 10.7 

 80 

 6.2 

 158 

 12.3 



Pribilof. 



1,224 

 83 

 6.7 

 217 

 .7 



w 



6.2 

 166 

 13,5 



VARIATIONS IN SIZE AND COLOR OF THE PRIBILOF FUR SEAL. 

 By Frederic A. Lucas. 



While the Pribilof fur seal varies in size, color, and proportions to such an 

 extent that were but a few individuals known, they might be held as belonging to 

 two distinct species; part of this, particularly the variation in color, is due to age. 

 The young pups are black above, with a few gray hairs on the head and neck; the 

 side of the neck is slightly tinged with gray and the greater part of the under surface 

 is dusky brownish gray. There is a spot of yellowish-brown at the axilla and the 

 region around the mouth is of the same color. 



Between the middle of September and the middle of October the majority of 

 pups have shed their black coats and assumed the silvery gray and white of the 

 "gray-pup" stage. Up to the age of two years the young of both sexes are of a 

 beautiful steel gray above, with the throat and belly white, the central portion of the 

 latter being suffused with chestnut. On the breast, at the base of each flipper is a 

 convex patch of gray which nearly meets its fellow of the opposite side, thus reducing 

 the white at this place to a narrow isthmus, connecting the throat with the under parts. 

 There is a dark spot at the anterior edge of the flipper and a light spot on the axil 

 this being retained for some time in the female. The white throat is very conspicuous 

 even at a distance, and indicates that the animals have not reached a killable age. 



The coloration deepens with age, the gray encroaching upon the white of the 

 throat and the chestnut deepening in intensity on the under side until it becomes rich 

 and dark, while the patches below the flippers unite to form a baud across the chest 

 the dark spots on the anterior edge of the flippers becoming a dull chestnut. 



Still later the chestnut under side gives place to gray with a slight chestnut 

 tinge, the old females being dark gray above and lighter gray below; this last with a 

 tinge of chestnut. There is a light patch on the center of the throat and a dark band 

 running across the breast from flipper to flipper. 



