MUSEUM OF COMPARATIVE ZOOLOGY. 37 



vast numbers at certain favorite places of resort, — usually isolated rocky 

 islands, — for the purpose of reproduction, where they spend several 

 weeks or months, when undisturbed, almost entirely on land. They being 

 eminently polygamous, the old males select their stations and assemble 

 around them a numerous harem, which they guard with the utmost 

 jealousy. Numerous bloody combats ensue between the rival males for 

 the possession of the females, or for favorite stations, and the roaring 

 of the males it is said can be heard for many miles. One young, 

 or at most two, are annually brought forth by each mature female, the 

 period of gestation being about twelve months. Captain Bryant's 

 account* of the habits of the northern fur seal renders unnecessary 

 a detailed account of the habits of any of the species here, especially 

 since the notes added to Captain Bryant's paper sufficiently indicate 

 the similarity of habits which all the species seem to share during the 

 important season of reproduction. 



One of the most striking features in their history is that at this period 

 both sexes pass weeks, and even months, without food or without often 

 visiting the water. Arriving at the breeding-grounds exceedingly fat 

 and unwieldy, they seem to be sustained by the fat of their bodies, they 

 finally leaving at the end of the breeding-season greatly emaciated. 



A similar fact has been long known in respect to the walrus, whose 

 period of fasting, however, seems to be shorter than that of the eared seals. 



In respect to breeding habits, the sea elephant (Macrorhinus elephan- 

 tinus) is the sole species of the earless seals which seems to quite 

 closely resemble the Otariadce. They as.-emble in a similar manner at 

 their breeding-grounds, and pass much of their time during the repro- 

 ductive period on the land, and probably without taking food; but the 

 accounts of travellers are on this point somewhat, contradictory. It 

 does not appear, however, that they are to so great a degree polyga- 

 mous. And they move on the land with great difficulty, and go but a 

 short distance from the water. 



Of the Genera and Species. 

 Of (lie Genera. — The genus Otaria was, as previously stated, pro- 

 posed to embrace all the eared seal> as a group distinct from the earless 

 seals, for which the name P/i oca was retained. But naturalists have 

 found it necessary, as our knowledge of these animals has incre ised, to 

 • S< - Part IF, beyond. 



