ELEPHAS PRIMIGENIUS.— MANDIBLE. 



137 



Fig. 17. 



Fig. 18. 



E. Asiaticus. (Collection of Royal College of 

 Surgeons, No. 26/5.) 



E. Africanus. Collection of Royal College of 

 Surgeons, No. 2847.) 



The so-called truncated chin which Falconer and others have referred to as diagnostic 

 of the Mammoth, will be also seen from the foregoing cuts and those on p. 135 to be by 

 no means regular, there being much variability, from an obsolete rostrum (figs. 4 and 7) 

 to the long beak of Woodcut, fig. 11, which is fully three inches in length, and grooved ; 

 indeed, the beak is variable in the recent species likewise ; and, like the angle of conver- 

 gence of the rami at the symphysis, it is not a reliable character in any one of the 

 living or extinct Elephants hitherto described. 



Horizontal and a8cending ramus. — The relative and absolute lengths of the horizontal 

 and ascending rami furnish some important comparisons in the different species. The 

 Mammoth and Asiatic Elephant display close affinities in these respects ; E. meridio- 

 nalis and E. Africanus are closely associated ; and E. antiquus and E. Namadicus are, 

 as far as the specimens I have examined extend, also come together, the two latter being 

 nearer to the two former than to the Meridional and African forms, where the disparities 

 in relative lengths between the horizontal and ascending rami are far greater than in the 

 other four. Again, there are less differences between the length of the horizontal ramus 

 and maximum width of the ascending ramus in the Mammoth, and also in the Asiatic 

 (but to a smaller extent in the latter), than in *E. antiquus, and notably E. meridionalis 

 and E. Africanus, as will appear presently. 



In point of depth of the horizontal ramus and. consequent length of diasteme, both 

 attain their maximum in the middle period of life, and decline in very old age, when the 

 teeth grow up and cover a space between them and the alveoli, which become absorbed, 

 so that the mandible is then not nearly so thick and deep as in younger individuals. 

 This is well seen in PI. VIII, fig. 3, which represents a very old individual, the last true 

 molar being more than half worn away, whilst the surrounding socket as shown, p. 122, 

 seems too large for the teeth. 



Symphjsial (jiitter and its foramina. — The wide spout or gutter of the mandible of the 

 Mammoth is, as far as I am aware, unequalled by that of any known species. There are 



