DEVELOPMENT OF THE SKULL IN THE LACERTILIA. 639 
Plate. 
Fig. 
Stage. 
I 
39 
7 
fi+L 3 
The same, through widest part of eyeballs. (4th ) 
U 111 V 
section).) 
8 
f 
The same, through back part of eyeballs. (5th j 
33 
” i 
section).^ 
„ 
9 
33 
The same, between eye and ear. (6th section) 
40 
1 
f 
The same, through fore part of ear-sac. (7th sec- ) 
” i 
tion).. ) 
„ 
2 
” 
The same, through middle of ear-sac. (8th section) 
3) 
3 
33 
Part of same object. Right side ....... 
33 
4 
33 
Part of same object. Left side. 
33 
5 
33 
Same head, near back of ear-sac. (9 th section) . 
33 
6 
33 
The same, at back of ear-sac. (10th section) 
r 
Head of nearly ripe embryo of Zootoca vivipara, 
7 
7 tli -j 
1^ inch long; head ^ inch, or 3 lines in length. 
Transversely vertical section through nasal sac. 
i 
(1st section). 
Q 
( 
The same, through fore part of eyeballs. (2nd 5 
55 
o 
” l 
section).j 
33 
9 
33 
The same, through middle of ear-sac. (4th section) 
f 
The same, through hinder third of ear-sac. (5th i 
33 
10 
” 1 
section). . j 
33 
11 
33 
Same stage of embryo : hyo-branchial arches 
41 
1 
f 
Nearly ripe embryo of Zootoca vivipara : skull. 
” l 
Upper view.) 
33 
2 
33 
The same. Lower view. 
3 3 
3 
33 
The same. Side view. 
33 
4 
33 
Longitudinally vertical section of head of same . 
33 
5 
33 
The same object, with brain removed. 
33 
6 
33 
Part of the same skull as figs. 1-3. Upper view . 
7 
( 
Transversely vertical section through the head of j 
33 
” l 
the same, between eyes and ears. (3rd section) j 
42 
1 
8th 
Lacerta agilis, adult male : skull. Upper view 
3 3* 
2 
33 
The same, seen from below. 
1 
diameters 
18 
18 
18 
15 
15 
45 
90 
15 
15 
20 
20 
12 
20 
14 
14 
14 
14 
14 
14 
14 
20 
MDCCCLXXIX. 
4 N 
