FAMILY CHELONID^. 5 



Total length, 70-0, 



Ditto of the shield, 68-0, 



The young of this species presents strong and numerous variations from the adult. The 

 skin, instead of being smooth, is roughened with tubercles. The ridges are composed of a 

 series of rounded tubercles. The head is larger in proportion ; the pupil vertical, and the 

 sternum VFith five longitudinal ridges. 



This gigantic species, which breeds on the Tortugas or Turtle islands, and on the Bahama 

 islands and keys, visits our coast sufficiently often to entitle it to a place in our Fauna. It 

 was first noticed on our coast in 1811, and described and figured by Dr. Mitchill. In 1816, 

 another individual of a large size was captured ofi" Sandy Hook, and is now in the American 

 Museum of New- York, set up in a very false and grotesque manner. A third species was 

 taken in 1824, in Massachusetts Bay, and is described in the Report cited above by Dr. Storer. 

 A fourth specimen was taken September 7, 1826, in Long Island Sound ; and another in 1840, 

 in Chesapeake Bay. 



The Leather Turtle, although a native of tropical American seas, is a great wanderer : it 

 has been seen on the coast of England, and in the Mediterranean. We are not in possession 

 of sufficient evidence to determine whether the large leather turtle seen in the Pacific and 

 Indian oceans belong to this species. The food of our turtle is said to consist of fish, shells 

 and marine plants. 



Lesueur is said to have described another species ? under the name of Dermochelis atlantica ; 

 but I have been unable to find the description. 



GENUS TRIONYX. Geoffroy. 



Shell without scales, and, together with the sternum, cartilaginous, and extending over the 

 edges into a flexible margin. Feet palmated, with three sharp claws. A corneous beak, 

 covered with fleshy lips. Nose produced. Vent near the extremity of the tail. 



Obs. The coverings of the animals of this genus are even softer and more pliable than the 

 preceding. The expanded ribs which form the upper shell do not extend to the margin, and 

 the under portion is equally undeveloped. They all live in fresh-water streams, and have the 

 reputation of being exceedingly voracious. 



