. ArSTEALIA>' >AT1JBAL HISTORr, 145 



All marsupials which have the rotating movement of the lower 

 arm-bones possess clavicles — the exception being the bandicoots. 

 The clavicles of the Diprotodons are exactly like those of the 

 wombat. 



It is necessary to state here that the shape of the ulna in the 

 Diprotodons resembles that bone of the elephant, the olecranon 

 process being little developed. 



The femur of the terrestrial marsupials, who progress by a suc- 

 cession of leaps, is generally slightly bent ; in the wombats (and 

 more or less in the phalangers) it is a remarkably straight bone, 

 very short, the shaft flattened (in the Diprotodon), and the distal 

 portion much expanded. The tibia and fibula in the phalanger 

 tribe enjoy much freedom of motion. The kangaroos have these 

 bones closely attached, and the great Diprotodon had so short a 

 tibia and fibula that I could not make up my mind for years to 

 accept fragments of these bones as belonging really to a tibia. 

 There is no doubt about them any longer, and a restored tibia 

 and fibula in the Museum collection, will convince even the most 

 sceptical. 



The OS calcis or heelbone of the Diprotodon resembles that of 

 the wombat and native bear. The digits were probably very 

 small, but I cannot say more about them at present, though we 

 possess bones which may turn out to be those of the toes of a 

 Diprotodon. 



The vertebra? of these great animals resembled again those of 

 the Phaseolarctos, or native bear, and the wombat — the first, or 

 atlas, consisting of two parts when young, never joining below, 

 not even in adult subjects, just as the atlas of living phalangers 

 remains permanently open below. 



The ribs of the Diprotodon were probably thirteen pair, rather 

 broad, and not unlike those of the wombat. The tail was short, 

 and wombat-like also. 



The numerous large bones hithei-to discovered are in almost 

 every instance a proof of being those of phalangers, either of the 

 wombats or Diprotodon family, and not a single bone or tooth, 

 indicates the existence in Australia of a large carnivore — larger 

 than the Tasmanian Thylacine. 



I shall now give a list of the animals hitherto discovered in a 

 fossil state, and arrange them in the following order : — 



Fam. Phalangistid^. 



To this family belong all the gigantic fossil mammals. The 

 following genera are represented : — 



GejS^us Dipeotodok. 



With two described species Z>. australis and D. hennettii. 

 The last-mentioned animal has lately been been found by Messrs. 



