244 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



Range. — Same as that of the genus. Observed on all 

 the islands of the Galapagos Archipelago (Hopkins Expe- 

 dition). 



Two adult skins and one immature skull are in the col- 

 lection from Albemarle and Narborough Islands. 



This is the most abundant seal in the archipelago and 

 breeds wherever found. The breeding season does not 

 appear to be confined to any definite time of year, as pups 

 of all ages were found at all the rookeries during our stay 

 of six months. January, February, and March, 1899, 

 were spent about the rookeries on Narborough Island, and 

 Elizabeth Bay, Albemarle Island; April, at the Seymour 

 Islands; and May, at Hood and Barrington islands. The 

 pups at all these localities were found to be of various ages. 



The most extensive rookeries are situated on the east 

 coast of Narborough Island, at Elizabeth Bay, Albemarle 

 Island, at Gardner Bay, Hood Island, at the Seymour 

 Islands, and on Barrington Island. The largest rookeries 

 are on Narborough Island. These are situated along the 

 whole east coast for a distance of about fifteen miles. 

 This stretch of coast is well sheltered, deeply indented by 

 lagoons and covered in many places by a heavy growth of 

 mangrove, thus forming ideal breeding grounds for Otaria. 

 The extensive rookeries at Elizabeth Bay are similarly 

 situated on mangrove-fringed lagoons in quiet water. 



The bulls do not appear to be polygamous, a bull being 

 usually associated with but a single cow. This apparent 

 absence of polygamy may be due to the lack of a definite 

 breeding season. 



In most localities the seals are fearless, and the cows and 

 pups allow themselves to be herded like cattle. So abun- 

 dant and tame are they that the five sailors comprising the 

 sealing crew of our schooner took twenty-one hundred 

 skins in about four months. Usually as many skins as 

 could be " flinched " in a day could be readily obtained. 



The sharks, chiefly the genera Carcarhinus and Galeo- 

 cerdo, are the worst enemies the seals have to contend with. 

 Their depredations are conflned largely to the pups, though 

 the latter genus is a serious menace even to the adults. 



