606 SKULL-CHARACTERS IN THE SOUTHERN SEA-ELEPHANT. [May 25, 



actually exceeds that of the Macquarie skull. To this difference 

 may be added the almost complete flatness of the palate, the 

 longer inter-palatine suture, the much more slender' pterygoid 

 process, the U -shaped palatal aspect of the premaxillse, and the 

 extremely narrow condyles. 



For this race as typified by the figured skull I suggest the 

 name M. I. crosetensis, of which Peters' undefined If. kerguelensis 

 is probably a synonym. The immature ' Erebus ' and ' Terror ' 

 skull, said to be that of a female, may belong to this race ; the 

 greater prominence of the tympanic region as compared with 

 the Crozet specimen, being not improbably a feature due to 

 immaturity. 



As the result of the foregoing comparisons, our information with 

 regard to local races of the Southern Sea-elephant, as definable 

 from skull- characters (and, with the pi'esent material, I can find 

 no others of any value), may be summai'ised as follows : — 



1. Macrorhinus leoninus typicus. Juan Fernandez. 

 Skull unknown. 



2. M. I. fcddandicus. Falkland Islands. Perhaps inseparable 

 from typical race. 



Skull long and narrow ; pala,te flat behind and hollowed in 

 front ; palatine suture long ; pteiygoid process small ; palatal 

 aspect of premaxilla V-shaped. 



3. M. I. macquariensis. Macquarie and (?) Chatham Islands. 

 Skull of the same general type as in the preceding, but the 



palate markedly hollow throughout, the palatine suture shorter, 

 and the pterygoid process longer. Condyles wide. 



4. M. crosetensis. Crozet and (?) Kerguelen and Heard 

 Islands. 



Skull short and wide, with the palate almost flat, the pterygoid 

 process very slender, the premaxillse U-shaped, and the condyles 

 narrow. This race is said to be the largest of all. 



In addition to these there may be a distinct i-ace inhabiting 

 Tristan d'Acunha. I know nothing of the Sea- elephants of the 

 South Shetlands. 



Although the Californian Sea-elephant {M. angustirostris) does 

 not properly come within the purview of the present communi- 

 cation, I may take the opportunity of mentioning that the fore 

 part of a skull at present in the British Museum shows such 

 difference in the palatal region from all the races of the Southern 

 form, that on this ground alone the Southern and the Northern 

 Sea-elephants appear entitled to be regarded as specifically 

 distinct. 



[Since this paper was read Mr. Rothschild has informed me 

 that he has evidence to show that the San Juan and Chilian Sea- 

 elephants are identical, and that migration formerly took place 

 between the San Juan and the Guadaloupe Island animals. If 

 this be so, I presume anguMirostris would be regarded as a 

 isynonym of leoninus, while falclandicus would become the 

 substantive name for the Southern species.] 



