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

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

 terior incisor of the upper jaw is narrovv, 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 šame reraarks apply to the first falše molar. The 

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

 in contact -vvith that \vhich 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. Temminckii, a much larger animal, 

 the šame teeth occupy only nine lines. llie 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, presentiug an unnatural enlargement of the facial 

 bones, accompanied with a most remarkable development of the homs, 

 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 preliminarj"^ remarks 

 upon the importance of the study of the skelcjon, in investigating 

 the natūrai 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 principai modifications in the general form 

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



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

 genera for the small proportion \vhich 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 muscularimpressions; but in the 

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

 nium presents a smooth rounded surface as in birds, corresponding 

 with the smooth unconvoluted surface of the simple brain contained 

 \vithin. 



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

 theWombat and Ursine Dasyure in \vhich it equals three-fourths the 

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

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

 tical in position, forras a right angle \vith 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 \vhich, as also 

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

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

 of the strong museles from tlie neck and back. 



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



