112 NOTE ON THE GENERA 3YGOMATURUS A¥TD NOTOTHERIUM. 



from this, the reasons urged against the identification with 



Nototheiiuni are both invalid. The first that no other animal is 



known by dental evidence to which t lie humerus figured by Sir R. 



Owen could be ascribed, would indeed be a weighty one, were all, 



or nearly all, the marsupials of tbe period made known by their 



teeth or otherwise That this is very far from being the case is 



clear from the new forms which have offered, and are still offering, 



themselves for discrimination. It may be added that the question 



with the writer was not whether a genus can be found to fit the 



bone, but whether the bone is found to fit Nototherium. Moreover 



lie is not at all affected by the demand made for dental evidence 



other than that already in the hands of his critic as will appear 



from the fact on which his reply to the second objection "is founded. 



That reply, in brief, is, that so far from there being any ' great 



difference 1 between the skulls of Diprotodon and Nototherium, the 



truth is they are much alike, The great difference objected in 



intention isgroundel on the assumption that Nototheriumis identical 

 with Zygomaturus. 



Until lately no reasons against an identification in favour of 

 which none have been given, could have been adduced by the writer, 

 but to him Nototherium and Zygomaturus are now entirely dilfercnt 

 animals. Therefore the humerus referred to the latter under the 

 name of the former by Sir R. Owen may possibly prove to belong to 

 it ; but however that may be, the humerus noticed by the writer is 

 certainly nototheroid, and most probably Nototherium. To sub- 

 stantiate an opinion so pertinaceously contradictory, some obser- 

 vations penned before the above criticism came to hand, are now 

 offered. 



The genus Nototherium was founded on a portion of a man- 

 dible, clearly indicating the former existence of a mammal for 

 which a name was requisite, but in if self incapable of yielding the 

 data necessary for discriminative purposes when genera or species 

 arc in question. More especially the tooth which, from experience, 

 we have learned to be the only sale guide to identifications in the 

 ,L, r roiij» to which the mammal belongs wa wanting, and whaf other 

 examples of Nototherium mitclielli wen* in our lutmis wmiM always 



