1. DERMOCHELYS. 9 
ture as in the Cryptodira; but in one adult skull the symphysial 
suture persists. The hyoid (according to Gervais) lacks the anterior 
cornua and the posterior are ossified proximally ; the body is ossified 
in its posterior half, and a small ossification is present on each side 
in front of the cerato-hyals, which are large and bony. 
Fig. 1, 
Nl 
a \ 
‘ ih he 
KUN \\ 
i, is. 
Skull of Dermochelys coriacea. 
The pectoral and pelvic girdles agree in all essential characters 
with the Chelonide ; but the limbs, in spite of adaptive similarity, 
differ in important points :—Thus, in addition to the shape of the 
