490 
ZOOLOGY. 
The vertebral column is now more distinctly marked off 
than inthe Batrachians ; a cervical and lumbar region being 
‘indicated in most reptiles except the snakes and turtles. Well- 
marked ribs exist in nearly all the vertebre of the trunk, 
except in the turtles, where the so-called ribs are possibly, 
Fig. 438.—Skull of a Tur- 
tle seen from behind, 
2, exoccipi- 
tal; 3, su raoceipital; 5, basi- 
5, protic, (pe ( e 
trosal) ; 14, ca rate.—A: 
basi-occipital ; 
aphenoi 
Gegenbaur. 
according to Gegenbaur, modified 
transverse processes. 
The skull of reptiles is much 
more like that of birds than of 
There is a single 
occipital condyle, and the lower 
jaw is articulated by the quad- 
rate-bone to the base of the skull. 
The primitive skull, or that part 
immediately enclosing the brain, 
has an incomplete roof, but still 
is more bony than in Batrachi- 
ans; while owing to the great 
size of the bones developed orig- 
Amphibians. 
1, 
inally in and from the palato- 
quadrate cartilage, but a small Ren 
part of the true skull is to be 
The parts forming the 
seen. 
a B 
g. 439.—Bones of the foot of a 
tlie (lizard) A, and an embryo 
B. f femur ; zt, tibia ; iP, , fibula; 
zs, upper, Zz, lower pieces of t 
sus ; ™m, metatarsns J-V, metatarsa- 
lia of the toes. 
he tar= 
-hyoid suspensorium in fishes (hyomandibular and symplectic 
bones) are, as in the Batrachians, entirely separate from the 
skull. 
While the limbs are, as a rule, absent in the snakes, the 
Zore legs always wanting, in. a few forms, as the pythons, 
