ALASKA INDUSTRIES. 693 



11 to 12 pounds and the length from 18 to 24 inches. On page 274 Mr. 

 Elhott gives the weight of the fur-seal pup of one day old as 5 to 7J 

 pounds and its length as 12 to 13 inches. In the length of the tail of 

 the fur seals given on the preceding page that of the adult male is said 

 to be 4 to 5 inches. In all our measurements the tail of the bull did not 

 exceed 2 to 2J inches. These are small matters, but they point to guess- 

 work rather actual investigation as a source of information and have 

 an importance in connection with larger mathematical i^roblems, with 

 the results of which we must take decided issue later on. 



The apathy here noted as shown by the mother seal is true after the 

 pup has become able to move about and care for itself. For two or 

 three days, liowever, the mother seal is greatly concerned for the wel- 

 fare of her pup. She will lift it out of the way of a trampling bull as 

 a cat would a kitten. She will not desert her newly born pup. After a 

 few days, however, she correctly infers that it can take care of itself 

 and only looks after it at meal time, though she apparently enjoys 

 having it sleep at her side. 



Page <)0: Probably Mr. Elliott's estimate that not more than 1 per 

 cent of the pups are crushed by the bulls is too low. Two or 3 per 

 cent would probably be nearer the truth. On the other hand, in our 

 preliminary report for 189G, we were in error in ascribing the greater 

 part of the early mortality of puj^s to trami^Iing by bulls. Most of 

 the natural deaths of young pups, occurring from July 20 to August 20, 

 are due to the attacks of a small parasitic worm (Uncinaria), which 

 lives in infected or filthy sandy areas. The larvte adhere to the fiir of 

 the mother and are swallowed by the i3up while nursing. The worm 

 develops in the small intestine, where it multiplies, sucking the blood 

 of the pup, which may die of weakness or ana^inia even when quite fat. 

 The ravages of the worm are j^ractically over by the end of August. 



Unfortunately Mr. Elliott records no observations of the rookery 

 grounds in August, and gives us no data by which the ravages of the 

 worm can be estimated for the years when the rookeries were at their 

 height. Our first records of its work are found in a photograph of 

 Tolstoi sand flat taken in 1891, when several thousand pui^s, unques- 

 tionably killed by the worm, were found there, and are shown in a pho- 

 tograph taken by Dr. Dawson. On this same rookery the presence of 

 innumerable bones of pups strewn over territory unocupied even in 

 1891 shows that the worm was at work prior to that date. It is proba- 

 ble that the ravages of the Uncinana are as old as the herd itself. 



The reference in the footnote accompanying this page to the effect 

 of the "sudden nip" of the surf as a cause of death among the pups is 

 apparently unwarranted. The close observations of the past two sea- 

 sons, and particularly of the season of 1896, covering the severe storms 

 of September and October, failed to disclose any casualties due to the 

 surf. The number of drowned pups found among the dead is insignifi- 

 cant, and the evidence points to imprisonment among the rocks, weak- 

 ness from hunger, or the attacks of the worm as the indirect causes of 

 the few deaths which are due to drowning. The windrows of dead 

 pups cast up by the surf at Tolstoi and Vostochni are not drowned pups, 

 but wormy ones washed from the rookeries by the surf. 



Page 61: The observations of the season of 1897 show conclusively 

 that the pup knows its mother's voice, even at the age of two days, and 

 can follow it unerringly. That the pup "noses around every mother 

 seal that comes in contact with them" does not prove the inability of 

 the puj) to recognize its own mother. The persistent and successful 



