BY C. W. DE VIS. 239 



examples, or nearly a third of the whole number of cranial and 

 appendicular bones of Phascolonus in the collection. 



Adverting to the smaller species — on the assumption that the 

 liviug P. platyrhinus is identical with the fossil P. mitchelli, as it 

 is said to be, the latter is the only recognizable species of its size 

 as yet recorded from the Darling Downs. P. thomsoni, Ow., is an 

 extremely doubtful species, uniquely represented, and dependent 

 for its validity upon a single character, the backward extension of 

 the symphysis, a character which varies with age and, in mandibles 

 of P. mitchelli, shows its inconstancy thus : — in one example it 

 extends to the fore lobe of m 3 , in four to the interval between m 3 

 and m 2 , in five to the hind lobe of m 2 , and in four to the interval 

 between m 2 and m 1 . P. thomsoni should, therefore, be expunged 

 from our lists. But whether it be so or not is of slight moment 

 in a question of appeal to bones other than those of the head. A 

 species which has left us but a single fragment of its jaw is not 

 likely to have handed down other parts of its skeleton ; at any 

 rate it is not entitled to priority of consideration over those whose 

 cranial remains are numerous. We may, then, for the present 

 proceed on the assumption aforesaid, namely, that there was but 

 one wombat of the size of P. platyrhinus to remit its limb bones 

 for study ; then as bones of a wombat of that size, showing the 

 like dimensional correspondence with the teeth of P. mitchelli as 

 that observed in the case of P. gigas, are extant, the question 

 simply is, are they, as the identification requires, fossilised bones 

 of P. platyrhinus. One answer alone is possible, they are not. 

 If not, then either the numerous cranial and mandibular remains 

 of platyrhine wombats referred to P. mitchelli in the Queensland 

 Museum, and there constituting it the commonest species, belong 

 to some undescribed species unknown in the British Museum, and 

 not to the species also most numerously represented by such 

 remains in the British Museum, or the identification is at fault. 

 It is now incumbent upon me to show that these bones, which 

 under the circumstances must necessarily be ascribed to mitchelli, 

 are not bones of platyrhinus. They comprise two humeri, three 

 femurs, a tibia, and two ulnas. 

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