148 



NOTOTHEKIUM 



Guscuses.i The dental formula is I f C iPm f M ^i- ; the last 

 premolar is a great blade-shaped tooth like that of Potorous. 



Ndtothcrium was a creature smaller than Dlprotodon, but still 

 of large size ; it is believed to have been a burrowing creature, 

 and to connect the Wombats with Dii>ri)tndim. More certainly 

 allied to the existing Wombat was Fliasrohni.HS, a Wombat as 

 big as a Tapir. 



Of extinct American Diprotodonts the Epanorthidae, already 

 referred to in connexion with the living Caenolestes, were the most 



FiH. 75. — yuotherinm mitchelli. Side view of skull. x |. (After OAven.) 



prominent forms. The genus U'panorthus occurs in the Santa Cruz 

 formation of Patagonia, which is believed to be Midcenc. The 

 incisors are three in the upper jaw ; and the single incisor of each 

 ramus of the lower jaw is a great chisel-shaped, cutting instrument. 

 Altdrrites is also typically Diprotodont hj reason of the large 

 projecting incisors of the lower jaw. It has a large cutting 

 tooth in the lower jaw, which appears to be the last premolar, 

 and is thus comparable to the great cutting tooth of the lower 

 jaw and of the upper jaw of the Extinct Phalanger, ThylacoUo. 



' (^uite recently [Pmc. Linn. Soc. N.S. IK 1898, p. 1) the carnivorous character 

 of Thijlncofco has been reasserted liy Mr. Broom. 



