80 STUDIES IN TASMANIA N MAMMALS, LIVING AND EXTINCT, 



succumbed to its wounds is exactly that required to effect 

 the amount of repair manifested by the broken clavicle, 

 which, by estimation, is only a few weeks at the outside. 

 A very careful examination of the skull and skeleton was 

 made prior to removal from the matrix, especially the 

 skull, and the conviction was formed that the horn had 

 been lost prior to the animals inclusion into the shallow 

 mud of the old lake floor. Now the horn was an epi- 

 dermal structure, and just what effect the chemical action 

 of the niarcasite and peaty marl would have had upon 

 it is not easy to say, but as seemingly soft wood, in the 

 form of roots of trees, manage to survive, and impress 

 the matrix with their outlines, some little indication of it 

 might have been expected had the weapon remained in 

 situ. We most carefully removed all the mud with our 

 hands from the nasal regions (without lifting the skull), 

 and no indication of the fighting weapon rewarded our 

 search, and accordingly wo concluded that the horn had 

 been torn from its platform prior to the animal's death. 

 In the modern rhinoceros this also happens, in extreme 

 cases, one instance being cited in which a rhinoceros drove 

 its horn through the side of an elephant, tore the horn 

 off, and both rhinoceros and elephant died. 



THE NASAL HORN. 



If a card of the shape shown in our illustration (fig. 

 1) is cut O'ut and placed upon the nasal platform of the 

 skull of Nototherium mitchelli, it will exactly cover the 

 area that might be presumed to form the attachment sur- 

 face for the base of the nasal horn. Its central portion 

 would be cut equatorially by the naso-nasal fossa (C), and 

 its right and left frontal aspects, by two nutrient fora- 

 mina (A, B). Working backwards upon the skull, we 

 discover that the ecto-carotid artery was immense, and 

 prior to sending forward its maxillary branch, gave up 

 some twigs to the vertex, as though to nouiish a second, 

 small horn, for which a frontal resting-place exists. After 

 passing the ant-orbital canal, the internal maxillary artery 

 ramified over the face, one portion going to supply the 

 enormous nasal septum and cartilage generally, a second 

 entered the nasal cavity, either in a distinct bony groove, 

 or, in some skulls, more plexiform, over the bony roof 

 of the nose, eventually passing upwards through the naso- 

 nasal fossa to feed the base of the horn. While a third 

 branch, seemingly the homologue of the lateralis nasi, 

 went through the lateral groove in the nasal boss, to supply 

 the horn with nourishment, and therefore means of re- 

 pair. 



