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Deinotherium, it is common to all the Cetacea, and is met with in a 

 slighter degree in the great Ant-eater and some others of the Edentate 

 order. The corresponding position of the foramen magnum presents 

 nearly the opposite extreme to man in the occipital scale, proposed by 

 Daubenton as a test of the intelligence of animals ; and the indication of 

 the limited capacity of the Toxodon thus afforded, is confirmed by the 

 very small proportion which the cerebral cavity bears to the zygo- 

 matic and maxillary arches and to the size of the spinal chord which 

 is indicated by the foramen magnum. A great proportion of the outer 

 table of the skull is broken away, exposing a coarse and thick diploe ; 

 but the form of the remaining parts, which are modified in relation to 

 the attachment of the muscles of the jaws, indicates that these were 

 powerfully developed. The general form of the skull, while it presents 

 certain points of resemblance with that of the aquatic Pachydermata, and 

 even of the Carnivora, has much that is peculiar to itself; but, upon 

 the whole, approaches the nearest to that of the Rodentia; and the 

 dentition of the Toxodon, as exhibited in the upper jaw, corresponds 

 with that which characterizes the Rodent order, but with certain devia- 

 tions, indicative of a transition to the Pachydermata ; a transition of 

 the most interesting character, inasmuch as there is an evident approach 

 to the Pachydermatous order, in the hoof-like claws, thinly covered 

 hide, and heavy proportions of the Capybara ; and some less obvious 

 affinities were long ago detected by Cuvier between the minutest genera 

 of Rodents and the gigantic Proboscidian Pachyderms. 



The teeth of the Toxodon consist of molars and incisors, separated by 

 a long diastema, or toothless space. In the upper jaw the molars are 

 fourteen in number, there being seven on each side ; the incisors four, 

 one very large, and one small, in each intermaxillary bone. 



The general form and nature of the teeth are indicated by the sockets, 

 and the structure of the grinders is exhibited in a broken molar, the last 

 in the series on the left side of the present skull ; and by another perfect 

 molar, the last but one on the right side of the upper jaw, which, though 

 not belonging to the same individual as the skull here described, un- 

 doubtedly appertains to the same species. 



