LEATHERY TURTLE. 13 



THIS remarkable species is distinguished from all the 

 other marine Turtles by the absence of horny plates upon 

 the body, head, and limbs ; which, instead of them, are 

 covered by a tough leathery skin. In this respect it bears 

 the same relation to the family to which it belongs, that 

 the different species of Trionyx do to the fresh-water Tor- 

 toises most nearly allied to them. This skin is perfectly 

 smooth in the adult ; but in young specimens it is covered 

 with hard tubercles. The head is more acute than in the 

 other marine species : it is somewhat triangular when 

 viewed from above, the part anterior to the eyes being 

 narrowed; the jaws are of immense strength, and the 

 edges very sharp; the upper one has three remarkable 

 notches, one in the centre, which is angular, and one on 

 each side at a short distance from the former, which are 

 rounded. The .lower jaw is scarcely sinuated at the 

 margin, and the point is very acute, and somewhat hook- 

 ed, corresponding with the central notch of the upper. 

 The nostrils are small, and perfectly circular. The eyes 

 rather large, opening nearly vertically, particularly in the 

 younger specimens. The view of the head here given is 



from a very large individual, of which the head and extre- 

 mities are in my collection. The carapace, or dorsal shell, 

 has seven distinct raised carinse, or ridges, which in the 

 adult are sharp, and slightly toothed : in the young they 



