Tertiary.-] PALEONTOLOGY OF VICTORIA. IMammalla. 



MTestler, and by swaying from side to side bringing the tree down 

 by the weight of the body applied by a power of grasping, given 

 in each animal by the rotating articulation of the radius or smaller 

 bone of the fore-arm allowing of pronation and supination as in a 

 man or monkey. The Diprofodon, having powerful incisor teeth, 

 could effect its object more easily by gnawing the timber so as 

 to weaken it, and thus make up for its legs and pelvis being of 

 the comparatively slender type of the Elephant rather than of the 

 unexampled width and strength of these parts in the Megatherium. 

 The anterior and posterior limbs of Diprotodon were not of very 

 unequal size as in the Kangaroo, but more like ordinary quadrupeds 

 as the Wombat, and the portions of the skeleton found indicate a 

 leno-th of about 10 feet and a height of about 6 feet. There are 

 only two well-marked portions of the skeleton in om- possession in 

 the National Museum collection, one a huge scapula., or blade-bone, 

 which, in this genus, is remarkable for its very narrow triangular 

 shape as in birds and reptiles, and for the base of the triangle 

 being below at the articular end instead of above ; it is traversed 

 by a very prominent keel or spine. The other is the distal end of a 

 huge humerus., or ami bone, 10 inches wide, presented by the late 

 Dr. Greeves, from near Lake Timboon. This bone, in Diprotodon., 

 has little medullary cavity, and the inner condyle is not perforated 

 as in Kangaroo and Wombat, agreeing in this respect rather with 

 some of the arboreal forms of living marsupials (Phalangista, &c.). 



This species nearly equalled in size the ponderous elejDhantine 

 marsupial, the Diprotodon Australis of New South Wales and 

 Queensland, but had obviously a much more slender or compara- 

 tively elongate head. This is shown by the longer and straighter 

 lower incisors with their consequent longer and narrower worn 

 surface, the longer and less inclined diastema in front of the molars, 

 and the smaller and naiTower molars ; the proportionate differences 

 of which are given above in detail. From tip of tusk to hind edge 

 of last molar is 17^ inches in our species, and about 20 inches 

 6 lines in D. Australis. 



In this species there is a much nearer approach to the Kangaroo 

 type of dentition, in the greater development of the fore-and-aft 

 I'idge from the middle of the posterior part of the anterior lobe 



DEC. IV. [ 9 ] B 



