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XI. On the Fossil Mammals of Australia. — Part VII. Genus Phascolomys: species 

 exceeding the existing ones in size. Bij Professor Owex, F.B.S. &c. 



Eeceived March 25, — "Read April 18, 1S72. 



In a former communication* I applied the cranial, mandibular, and dental characters of 

 the existing species of Wombat to the determination of the fossil species resembling 

 them in size; in the present are given the results of an easier task, viz. the determi- 

 nation of extinct Wombats of markedly superior size to any now living ; and I shall 

 describe the fossils as the species they represent progressively predominate in bulk. 



§ 1. Phascolomys medius, Ow. — This species is represented by a lower jaw, fractured 

 at both ends, presented by Sir Charles Nicholsox, Bart., to the Geological Society of 

 London; also by the fore part of the upper jaw of two individuals and by the right 

 ramus, fractured at both ends, of the lower jaw, obtained by Edward S. Hill, Esq., from 

 freshwater deposits exposed in the bed of a tributary of the Condamine River, at Eton 

 Vale, Queensland: the latter were submitted to me in 18G5, and have been liberally 

 presented, with other Queensland fossils, to the British Museum by Sir Daniel Cooper, 

 Bart. All these fossils are in the usual heavy, petrified, rolled, and more or less mutilated 

 condition of such remains from the above formation and locality. 



The first to be described (Plate XXXII. figs. 2-7) consists of so much of the premaxillary 

 (22) and maxillary (21) bones as includes the sockets of the incisors (^) and of the first three 

 molars {d 3, d 4, m 1, fig. 2), with part of that of the fourth, m 2. The incisors are broken 

 off at the level of their alveolar outlets (fig. 6, i) ; the first and second molars, left side, 

 show their natural grinding-surface ; part of that of the following tooth is broken ; the 

 rest of the molars are more or less mutilated or wantin£r. 



The superiority in size of the present extinct species to the two largest of the 

 existing Wombats will be seen by comparing the above-cited figures, especially fig. 2, 

 Plate XXXII., with the corresponding parts of the skull of Phascolomys latifrons (ib. 

 fig. l)and oi Phascolomys 'platyrhinus (Plate XXXIII. fig. 1); it needs not to introduce 

 the smaller Tasmanian Wombat into the comparison. 



The following admeasurements give the degree, or value, of the character from the 

 size of teeth and extent of diastema of the species above cited: — 



I P. medms. 

 iDches. lines. 



P. 2i^uti/r7iimis. 

 inch, linos. 



P. laiifronx. 

 inch, lines. 



1 



1 



9 



1 



1 



0 



9 



