26 TESTUDINATA.-— SPHARGIDiE. 



united so as to be scarcely distinguishable, and 

 incased in the common integument. They all 

 inhabit the ocean, which they never leave except 

 for the purpose of depositing their eggs. 



The Sphargidce, or Leatherbacks, have the 

 bony structure of the carapace and plastron in- 

 vested with a leathery skin instead of horny 

 plates. In the young animal this is tuberculous, 

 but in adults it is smooth, though marked with 

 several ridges, slightly serrated, which run down 

 through the whole length of the carapace and 

 plastron. 



Genus Sphargis. (Illig.) 



The one or two species which belong to this 

 genus compose the whole Family. Their re- 

 maining characters may be thus summed up : the 

 carapace has seven longitudinal ridges, the plas- 

 tron live ; the j)addles have no distinct nails ; the 

 muzzle is pointed ; the jaws are of great power ; 

 the upper has a sharp tooth on each side near the 

 tip, behind which is a deep notch, and another 

 triangular notch in front separates the two teeth, 

 which receives the sharp up-turned point of the 

 lower mandible ; the opening of the eyelids is 

 almost vertical, and when closed the edge of the 

 posterior (answering to what is ordinarily the 

 lower) overlaps that of the anterior ; the fore 

 limbs are much more developed than the hind, 

 and are of great length and breadth. 



The species that inhabits the Mediterranean 

 {^Sphargis coriacea, Linn.) has occasionally strayed 

 to the shores of our own islands. Some of the 

 specimens taken here have weighed seven hundred 



