84 STUDIES IN TASMANIAN MAMMALS, LIVING AND EXTINCT, 



crested Nototheria are made a distinct group of, and not 

 regarded by us as possible sexual skull variations. 



To close this comparative study, we must now recall 

 the stages outlined- above, and see how they agree with 

 the conditions found in the extinct Nototheria and 

 Dvproiodons. 



1. The Kangaroo best agrees with Diprotodon. 



2. Tho Wombat's cranial platform is most closely 



simulated by Nototherium m/itchelli, in both sexes, 

 to a slightly variant degree. There are>, however, 

 traces of the primitive state in which the inter- 

 parietal interposed, as in the Kangaroo and 

 Native Bear. This, however, is only visible 

 under a lens. 



3. The crest of the Native Bear is found in Noto- 



therium tasmanicum, in which skull the whole of 

 the shield-shaped interparietal area has become 

 an open fossa for the implantation of a moiety 

 of the ligamentum nucha?, and accordingly, the 

 crest arises at the occipitoparietal ridge, as the 

 direct result of the suppression of the inter- 

 parietal from its true ancestoral position, as a 

 moiety of the vertex. 

 In our section devoted to the taxonomy of the groups, 

 we shall deal fully with the relationships of the several 

 known and recognised Nototheria — the present note how- 

 ever, being osteological, was best interpolated here. 



As Professor Owen's description of the Notothertan 

 skull covers so much ground, we shall only add such items 

 as his material did not permit of passing in review. 



THE PALATE, ETC. 

 The whole palate is, in essence, that of the Hairy- 

 nosed Wombat, and is not so closely allied to that of the 

 Tasmania.n Wombat — namely, the prepalatine fossa is the 

 same, although less deeply impressed, and the second pair 

 of molars are not carried inwards upon the palate, but 

 remain practically in the same alveolar curve as their 

 fellows. 



The total length of the bony palate is 305 mm., and 

 that of the tooth line — 175 mm. The widths between 

 successive teeth, measured between the centres of the teeth 

 named, are as follows <:• — - 



Between Premolars (centres) 55 mm. 



Molars I, „ 64 ,, 



Molars II. ,, 74 „ 



Molars III. ,, 75 ,, 



Molars IV. „ 75 ,, 



