722 THE CARNIVORES 



eared seals in passing a period of several weeks, during the breeding season, en- 

 tirely on land, and without partaking of any kind of food. As a rule there is but a 

 single young one produced at a birth, and there is never more than a pair. All the 

 seals are in the habit of spending a large portion of their time basking in the sun on 

 sandy beaches or ice floes. 



Their food, of which a large quantity is necessary, consists chiefly of fish, but 

 also comprises crustaceans and mollusks; and most of the species, like the eared seals, 

 are in the habit of swallowing a number of pebbles. 



As may be at once seen from the total absence of external ears and the struc- 

 ture of the hind-limbs, these seals are more specialized creatures than the eared 

 seals, and are thus more completely adapted for an acquatic life. This is especially 

 shown by the long period these animals can remain under water without coming up 

 to breathe. According to Dr. Robert Brown, the average time of a seal's submer- 

 gence is from five to eight minutes, while the limit is set down by the same observer, 

 at a quarter of an hour. Other authorities state, however, that the time may be 

 extended to as much as twenty or thirty minutes. The sounds uttered by seals are 

 various, in some cases taking the form of a kind of barking note, while in others they 

 assume a more bleating tone, or even resemble the cry of a child; the note of the young 

 being always more plaintive and less hoarse than that of the adult. In no cases, how- 

 ever, do they utter barking roars comparable to those characteristic of the eared seals. 



The strange circumstance that young seals take to the water reluctantly, and 

 have to be taught the art of swimming by their parents, would alone appear to be a 

 sufficient indication that seals are originally descended from land Carnivores. Among 

 some species the young remain entirely on the land or the ice for the first two or three 

 weeks of their existence, or until they have shed their first coat of woolly hair. 

 Numbers of seals are destroyed by the Polar bear, while others fall victims to the 

 rapacious killer- whale. Others again are frequently destroyed by being jammed be- 

 tween ice floes; and it is stated that thousands are sometimes killed by this means. 

 The reduction in their numbers by all these causes are, however, trivial compared to 

 those inflicted by man, who, according to Mr. J. A. Allen, requires about a million 

 and a half to supply his annual needs. So reckless, indeed, has been the destruction 

 of seals, that some species are already well-nigh exterminated, while others have 

 been so reduced in numbers as to render their pursuit no longer profitable. 



Several species of seals inhabiting the Northern Hemisphere are in the habit of 

 making long migrations, moving southward to avoid the intense cold of winter, and 

 returning northward in summer; such migrations being most marked in the Green- 

 land and the hooded seal. These movements have been carefully observed by 

 Mr. J. C. Stevenson, on the Atlantic coasts of North America. The southern mi- 

 gration commences soon after the frost sets in; and at this season, he writes, " a fish- 

 erman, posted as sentinel on some headland commanding an extensive sea view, com- 

 municates to the hamlet the first indication of the approaching host, the vanguard 

 of which invariably consists of small detachments of from half a dozen to a score of 

 seals. Such parties continue to pass at intervals, gradually increasing in frequency 

 and numbers during the first two or three days of the exodus, by the end of which time 

 they are seen in companies of one or more hundreds. The main body is now at hand, 



