327 



although seven molars are successively developed in this genus on each 

 side of both jaws : we seem, therefore, to have another distinctive cha- 

 racter of the great extinct Kangaroos in the extent of their molar series, 

 though this was probably a transient one ; the number of molars de- 

 creasing with age. The depth of the jaw in the present fragment below 

 the penultimate molar is one inch and a half: the arterial canal destined 

 for the base of the socket of the large procumbent incisor, may be seen 

 below the great dental canal on the anterior fractured end of the fossil, 

 but the socket itself has not reached so far back. 



From the alluvial or newer tertiary deposits in the bed of the Conda- 

 mine River, west of Moreton Bay, Australia. 



Presented by Lieut. -Col. Sir T. L. Mitchell, C.B. 



1518. The right ramus of the lower jaw of a small species of Kangaroo, having 



the premolar and four true molar teeth in place and use. It presents a 

 longitudinal indentation on the outside of the alveolar processes of the 

 first two molars: the section of the jaw anterior to the molar series 

 shows the socket of the great procumbent incisor to have extended 

 further back than in the fossil. Purchased. 



1519. A portion of the right superior maxillary bone of the Macropus Atlas, 



containing six molar teeth : the small anterior deciduous molar is frac- 

 tured ; the crown of the permanent premolar, the great antero-posterior 

 extent of which distinguishes the present extinct species from the Ma- 

 cropus Titan, is exposed in its closed alveolus from within ; the anterior 

 end of this premolar is irregularly notched : the sixth molar had not cut 

 the gum ; its posterior half is lost : the molars in place correspond in 

 character with those in No. 1513, which has formed part of a similar im- 

 mature animal. 



From one of the caves in Wellington Valley, Australia. 



Presented by Count Strzelecki. 



1520. A smaller portion of the right superior maxillary bone of an imma- 

 ture individual of the Macropus Atlas, with three molar teeth in situ, 

 and the crown of the permanent premolar exposed by the removal of the 



