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obtuse ; the orbit is smaller ; tlie temporal ridges generally meet 

 near the occiput, or are separated by a very narrow space ; the an- 

 terior incisor of the upper jaw is narrow, and has but one notch ; 

 the next incisor on each side is considerably larger, longer, and 

 stronger than in G. Temminckii, and moreover differs in having its 

 edges even; the same remarks apply to the first false molar. The 

 incisors and molars here form a continuous series, each tooth being 

 in contact with that which precedes, and that which is behind it. 

 The most important difference perhaps which exists between the 

 two species in question consists in the much larger size of the molar 

 teeth in the smaller skull, the five posterior molars occupying a space 

 of ten lines in length, whereas in G. Temmi/icUl, a much larger animal, 

 the same teeth occupy only nine lines. I'b.e above are the most pro- 

 minent characteristic differences in the two species, though several 

 other minor points of distinction may be observed. 



Mr. Blythe called the attention of the Meeting to the skull of a 

 Cumberland Ox, presenting an unnatural enlargement of the facial 

 bones, accompanied with a most remarkaljle development of the horns, 

 one of which measured four feet in circumference at its base. 



The reading of Professor Owen's paper " On the Osteology of 

 the Marsupialia," was completed. After some jjreliminary remarks 

 upon the importance of the study of tlie skeleton, in investigating 

 the natural groups of this order and the determination of the inter- 

 esting fossils of Australia, Professor Owen proceeded in the first 

 place to point out the principal modifications in the general form 

 of the skull as observed in the various genera of marsujjial animals. 



" The skull," says Professor Owen, " is remarkable in all the 

 genera for the small proportion which is devoted to the protection 

 of the brain, and for the great expansion of the nasal cavity imme- 

 diately anterior to the cranial cavity. 



" In the stronger carnivorous species the exterior of the cranium 

 is characterized by bony ridges and muscular impressions ; but in the 

 smaller herbivorous species, as the Petaurists and Potoroos, the cra- 

 nium presents a smootli rounded surface as in birds, corresponding 

 with the smooth unconvoluted surface of the simple brain contained 

 within. » 



" The breadth of the skull in relation to its length is greatest in 

 the Wombat and Ursine Dasyure in which it equals three-fourths the 

 length, and least in the Perameles laffotis in which it is less than 

 one-half. The occipital region, which is generally plane and ver- 

 tical in position, forms a right angle with the upper surface of the 

 skull, from which it is separated by an occipital or lambdoidal 

 crista. This is least developed in the Myrmecobius, Petaurists. 

 and Kangaroo, and most so in the Opossum, in which, as also 

 in the Koala, the crest curves slightly backwards, and thus changes 

 the occipital plane into a concavity, well adapted for the insertion 

 of the strong muscles from the neck and back. 



" The upper surface of the skull presents great diversity of cha- 



