BY C. W. DE VIS. 163 



Length of molar series with premolar 174 



Length of premolar 14 



Breadth of premolar 10 



Length of m 4 48 



Breadth of m 4 30 



Length of incisor, upper edge 47 



Breadth of incisor, longitudinal, at upper margin 



of outlet 34 



Breadth of incisor, transverse 22 



Length of symphysis 194 



Judging by the general facies and by the molars only, and 

 allowing for changes wrought by age and differences possibly 

 contingent upon sex, the Nototherium jaw, with which the present 

 one might readily be identified, is that named by Owen Noto- 

 therium victorice. So great is the resemblance between them that 

 the writer long hesitated to think them distinct. Possibly they 

 are not so, but after much pondering he has come to the conclusion 

 that he would not be justified in assuming an identity for which, 

 in the absence of the necessary tests, there is no positive warrant. 

 Still it would be by no means surprising to find that the essential 

 characters of N. victorice, at present unknown, associate it with 

 Euowenia. 



The family name Nototheriidce has been imposed by the talented 

 author of the British Museum Catalogue of Fossil Mammals, 

 Vol. V., upon the single genus Nototherium as understood by Owen, 

 and in a larger sense that name is admissible, nay inevitable. For 

 the genus Diprotodon Mr. Lyddeker writes as a higher term Dipro- 

 todontidce. This proposal to erect Diprotodon into the type of a 

 distinct family must be ascribed to the unfortunate confusion 

 perpetuated between Nototherium and Zygomaturus. Compared 

 immediately with Zygomaturus, Diprotodon stands indeed suffi- 

 ciently far aloof to be invested with family rank, but when Noto- 

 therium in its true characters is placed in position between the 

 two, Diprotodon seems to be nothing more than a member of the 

 Nototheriidce. However that may be, the term Diprotodontidce is 



