266 MB, G. E. H. BARRETT-HAMIIiTON ON" [Feb. 16, 



February 16, 1897. 



Prof. Geoege B. Howes, F.Z.S., in the Chair. 



Dr: E. C. BtirUng, F.R.S., C.M.Z.S., exhibited some bones, casts, 

 and photographs of the large extinct struthious bird from the 

 Dijjrotodon-heds at Lake Calhibonna, South Austraba, which had 

 been recently discovered and named by him Genyornis neivtoni, 

 and gave a history of the principal facts connected with its 

 discovery '. 



Mr. G. E. H. Barrett-Hamilton, F.Z.S., exhibited a pair of tusks 

 of the Pacific AValrus {Trichechus obesus), which he had purchased 

 at Petropaulowsk, in Karaschatka. He regretted that be was unable 

 to exhibit the skull, which he had also purchased, but which had 

 not yet reached England. The present tusks were the largest of a 

 good many which he had seen at Petropaulov^sk ; and it was a 

 peculiarity of that place that the hunters there seemed to bring in 

 the complete skulls of those which they kill, whereas the tusks for 

 sale on the Alaskan side of the Pacific were, usually, removed 

 from the skulls. This, however, was not a matter of surprise, 

 considering the weight of the heads when complete. 



The Pacific Walrus was not well known to English naturalists ; 

 and Mr. Barrett-Hamilton stated that he could find no tusks of 

 this species either in the British Museum or in the Museum of 

 the E/oyal College of Surgeons. 



He considered that the Pacific Walrus was a good species or at 

 least subspecies, and that the characters pointed out by Mr. J. A. 

 Allen, in his ^Monograph of Xorth American Pinnipeds, to dis- 

 tinguish it from the Atlantic form were correct. He regretted, 

 however, that he himself had uot had the good fortune to see the 

 Walrus of the Pacific in life, as they were now exterminated in the 

 parts of the North Pacific in which he had travelled. The tusks 

 of the Pacific Walrus were very much larger thau those of the 

 Atlantic species, and Mr. Barrett-Hamilton stated that he had 

 seen nothing in London w bich at all approached the size of the 

 tusks now exhibited. In the Pacific, however, be had heard of 

 the occurrence of larger specimens. The animal itself was also 

 larger thau the Atlantic form, aud, according to Mr. Allen, had a 

 very different facial outline. Besides some differences in the 

 skulls by which the two species might be distinguished, the tusks 

 in the Pacific form were usually more or less convergent, and 

 Mr. Barrett-Hamilton had seen tusks which actually overlapped. 

 *' In the Atlantic species the tusks were, as a rule, divergent ; while 



' On this subject 8ee ' Nature ', vol. 1. pp. 184, 206 (1894). 



