448 CHELONIA. 



jaws. It differs, however, from both, by zoological characters easily 

 appreciable. 



Erom Lepidochelys it differs in the relative number of the claws, and 

 also by the same structural characters of the head which distinguish 

 it from Thalassochelys. 



Its nearest relationships are, however, with Ghelonia, if we take the 

 cephalic plates into consideration. The very great development of the 

 anterior flippers may acquire a generic value from the moment a second 

 species should be found presenting the same feature. 



EUCHELYS MACROPUS, Grd. 



(Plate XXXI, figs. 9-11.) 



Spec. Char. — Uniform blackish-brown above, with the edge of the 

 carapax and the flippers whitish or yellowish ; beneath yellowish, 

 with a black patch on each flipper. 



Syn. — Testudo macropus, Walb. Chelonogr. 1782, 112. 



Testudo mydas, ScHCEPFF, Hist. Testud. 1792, 73. Tab. XVii, fig. 2.— Latr. Hist, 

 nat. Kept. I, 1802, 22. Tab. i, fig. 1. 



Observ. — ^The above synonyms, we dare say, are but a portion of 

 those that may hereafter be referred to this species when its natural 

 history shall have been better investigated, and the various authors, 

 who have treated this subject, better understood, a task which at pre- 

 sent was premature to perform. For, it must be remembered that the 

 only materials at our disposal are two immature specimens, one of 

 which we have caused to be figured on the accompanying Atlas, and 

 from which the following description is made. 



A great similarity is likely to be found between the young of this 

 species and Chelonia viridis, and we are inclined to think that they 

 have often been taken for one another. One character, however, will 

 always be a sure guide : we allude to the presence of two nails to 

 each flipper in Euclielys macropus, and one only in Chelonia viridis. 



Authors, when speaking of Ghelonia viridis, sometimes ascribe to it 

 one nail to each flipper, and at others, two, without further inquiry 

 into the value of that structure. 



4 



