322 PROCEEDINGS OF METROPOLITAN SOCIETIES. 
existence of two radiating centres of hair on its enormous forehead. 
The body was stated to have offered nothing remarkable, either in 
size or external structure. Professor Owen then concluded his pa- 
per on the osteology of the Marsupiata, describing the remainder of 
the skeleton ; and he observed that he found it necessary to institute 
the minute researches and enter into the detailed descriptions which 
he had done, in order to enable others as well as qualify himself to 
undertake the determination of fossil marsupial remains, some valu- 
able specimens of which had lately been entrusted to his care by the 
enterprising Australian traveller, Major Mitchell. 
Novemser 13th.—Mr. Waterhouse read a paper on the marsu- 
pial genus Petaurus, which he considered divisible into three marked 
sub-genera, distinguished by differences in their dentition. M. Des- 
maret had already separated the Pygmy Petaurist (Dide/phis pyg- 
meus, Shaw), under the name Acrobatus, which he accordingly 
adopted: this sub-division possesses thirty-six teeth in all, the pecu- 
liarities of which are stated in the Regne Animal. The Great Pe- 
taurist (P. loquanoides, Desm. ; Didelphis petaurus, Shaw) formed 
the type of the second sub-genus, comprising several species, to 
which the appellation Petaurus was proposed to be restricted: the 
members of this group have in all thirty-four teeth. Lastly, the 
Sciurine Petaurist (P. sciurea), with three or four others, were 
brought together under the designation Belidea, possessing forty 
teeth, which exhibit considerable modification when compared with 
those of the preceding: it had also a perfect bony palate, which 
was not the case with the others. A new species was described 
under the denomination of Belidea breviceps. Mr. Waterhouse 
then proceeded to offer some remarks on the American Badger of 
authors ( Nules Labradoriens, Richardson), of which he exhibited 
some crania, together with specimens of that of the common Euro- 
pean Badger. The differences were so very considerable that he 
could not.hesitate about the propriety of making a separate mini- 
mum sub-division of the American animal, for which he proposed 
the appellation Taxidea. In the European Badger, the carnivo- 
rous grinder is small, and the tubercular exceedingly developed, the 
carnivorous character of dentition being reduced to its minimum in 
this species, of all the Carnivora which possess but one tuberculous 
molar. In the American Badger the carnivorous grinder is in- 
creased, and the tubercular reduced to an equality of size ; the false 
molars, also, are more trenchant ; the lower jaw is not locked in its 
socket, as in the true Badgers ; and, finally, the skull is very diffe- 
rently formed, being widest posteriorly, where it is abruptly trun- 
cated, as in the majority of eminently fossorial mammalia: its ante- 
rior claws are likewise much more powerful than in the European 
Badger, altogether indicating an animal which burrows with still 
greater facility, and which subsists on a more carnivorous regimen. 
Professor Owen then described the cranium and dental characters of 
the Koala ( Phaseolaretos), from specimens of three different ages, 
the dentition of this genus haying never been before completely de. 
