350 



ZOOLOGY 



SECT. XIII 



In the Chclonia (Figs. 901, !)i)2) all tho bones, including the 

 quadrate, are solidly connected together. Transverse bones 

 (ectopterygoids), lacrymals, orbitosphenoids and alisphenoids are 

 absent. The place of alisphenoids is taken to a certain extent 

 by vertical downward plate-like extensions of the parietals, the 



Pmx 



Fin. non. — Skull of Sphenodon. A, Dorsal ; H, ventral ; C, left-sided view of skull of 

 Sphenodon, x'.l. Cnl . Ci.luiiiella aviris ; Cond. occipital condyle; E. P. ectopterygoid ; 

 _/•'. frontal; ./«(/. jugal ; M(u:. luaxilla ; jWt. nasal; A'c. anterior nasal opening; Pal. 

 palatine; Par. parietal; Pi/;,', preniaxilla ; Prf. prefrontal; Pt.f. post-frontal and post- 

 orbital; P<f7. pterygoid or endoptu-j-goid ; Q. quadrate and quadrato-jngal ; S»/. sfpianiosal ; 

 Vo. vomer. (Fi-om the Cambridfie Natural Ilintory.) 



lower part of the plates repi^esenting the epipterygoids of 

 Lizards. There may be open temporal fossie, the inferior boundary 

 of which {inferior femporrd arch) may be incomplete owing 

 to the absence of the quadrato-jngal, or the entire temporal 

 region may be covered over (Turtles, Fig. 992) by a sort of false 



