DINOTHERIUM. Ill 



tion of the tusks, such as are found in no other Uving or 

 fossil animal. 



The form of the molar teeth, PI. 2. C. Fig. 3, approaches, 

 as we have stated, most nearly to that of the molar teeth in 

 Tapirs ; but a remarkable deviation from the character of 

 Tapirs, as well as of every other quadruped, consists in the 

 presence of two enormous tusks, placed at the anterior ex- 

 tremity of the lower jaw, and curved downwards, like the 

 tusks in the upper jaw of the Walrus. (PL 2. C. 1. 2.) 



I shall confine my present remarks to this peculiarity in 

 the position of the tusks, and endeavour to show how far 

 these organs illustrate the habits of the extinct animals in 

 which they are found. It is mechanically impossible that a 

 lower jaw, nearly four feet long, loaded with such heavy 

 tusks at its extremity, could have been otherwise than cum- 

 brous and inconvenient to a quadruped living on dry land. 

 No such disadvantage would have attended this structure in 

 a large animal destined to live in water ; and the aquatic 

 habits of the family of Tapirs, to which the Dinotherium 

 was most nearly allied, render it probable that, like them, it 

 was an inhabitant of fresh-water lakes and rivers. To an 

 animal of such habits, the weight of the tusks sustained in 

 water would have been no source of inconvenience; and, if 

 we suppose them to have been employed, as instruments for 

 raking aild grubbing up by the roots large aquatic vegeta- 

 bles from the bottom, they would, under such service, com- 

 bine the mechanical powers of the pick-axe with those of 

 the horse-harrow of modern husbandry. The weight of the 

 head, placed above these downward tusks, would add to 

 their efficiency for the service here supposed, as the power 

 of the harrow is increased by being loaded. 



The tusks of the Dinotherium may also have been applied 

 with mechanical advantage to hook the head of the animal 

 to the bank, with the nostrils sustained above the water, so 

 as to breathe securely during sleep, whilst the body remain- 

 ed floating, at perfect ease, beneath the surface : the animal 



