214 MABSTJPIALIA. 



50051. The greater part of the right ramus of the mandible, showing 

 the four true molars ; from the same locality. 



Presented by G. F. Bennett, Esq., 1879. 



Macropus anak, Owen '. 



Syu. Protemnodon anak, Owen 2 (in parte). 

 Protemnodon og, Owen 3 . 

 Sthenurm atlas, Owen 4 (in parte). 



This species was founded upon a mandibular ramus, agreeing 

 very closely in structure with the mandible of M. brehus, but of 

 inferior size, and having no hind talon to m . 4. Other specimens 

 have, however, a small talon, and thus connect the typical form with 

 the slightly larger one described by Owen as Protemnodon og, which 

 may apparently be regarded merely as a variety. The confusion 

 noticed under the head of Sthenurus atlas in regard to the proper 

 upper dentition of that species led Owen to figure the upper jaws of 

 the present species under that name, while the proper upper jaws 

 of S. atlas were referred to the present species (*). 



In the two complete maxilla? the length of the cheek-series is 

 0,070 and 0,072 ; the length of the last three molars being 0,045 ; 

 but since other specimens show that the latter dimension varies 

 from 0,043 to 0,046, it is evident that a larger variation would be 

 found in the length of the complete series, if we had more complete 

 specimens. In the mandible the length of the cheek-series varies 

 from 0,057 to 0,071. 



This species is apparently very closely allied to M. brehus, there 

 being only a slight difference in size between the largest individuals 

 of the former and the smallest of the latter. 



Hub. Queensland, South Australia, and New South Wales. 



TJie following specimens include those referred by Owen 

 to Sthenurus atlas. 



45934. Part of the right maxillary region, showing the five cheek- 

 (Fiij.) teeth ; from the Pleistocene of South 'Australia. Figured 



1 Proc. Geol. Soc. vol. xv. p. 185 (1859). 2 Phil. Trans. 1874, p. 275. 



' Ibid. p. 277. 4 j f>ic j p 965. 



Ap;irt from all other evidence it is quite certain that tlie upper premolars 

 of the under-mentioned specimens could not have been opposed to j^l of 

 Sfhevurus atlas, while they agree precisely with the corresponding tooth of the 

 so-called Profemnodon anak. 



