OF THE SKULL IN THE COMMON SNAKE. 
407 
Seventh Stage. Snakes six weeks old, 7§ inches long. 
Being informed by Professor Huxley that there was cartilage in the distal parts 
of the Snakes hyoid or lingual region, I made diligent search both in early stages and 
in the adult : the evidence obtained was negative. 
Knowing well that feeble parts are often lade in budding forth, and early in fading, 
I considered it to be the best chance for finding hypo-hyal or hypo -branchial rudiments 
in the Snake to look for them in well-grown young. 
I thus take this for my seventh stage : there has been plenty of time for such carti- 
lages to appear, but none for then’ vanishing : the result is the same ; I can find no 
hyaline cartilage whatever between the distal parts of the mandible and the larynx ; 
all the floor of the mouth with the forked tongue and its sheaths are membranous. 
The other parts need have no further notice ; there need be no intermediate stage 
for them between the ripe young and the adult. 
Eighth Stage. Skull of the adult Snake. 
There are several reasons why the skull of the adult Snake should be worked out 
exhaustively, — in the fight of the history of its development. 
One reason is, that the “ Ophidia ” are a large and important order of the Saurop- 
sida, and to know one is to know all, so uniform are they, save in easily understood 
specializations. 
Beginning at the Amphisbsense and Anguians, if we run up the Laeertian Order, we 
shall find that their skull also can be read off in the light of that of the Snake. 
The skull of other groups also, fossil or recent, will be more intelligible when once 
this kind is known ; for the Snake’s skull is at once extremely simple, and yet marvel- 
lously specialized : some things in it stand almost still, whilst others run to the utmost 
stretch of their morphological tether.' 1 ' 
The skull of the adult Snake is irregularly oblong, flat above in its fore part, and 
sub-carinate below ; but the hinder part is gently convex both above and below 
(Plates 32 and 33). 
The orbital and occipito-otic regions are about equal ; the nasal region is about 
half the length of the others. 
The gently bi-convex, transverse, occipital cincture articulates with the atlas by a 
transversely oval condyle (Plate 32, fig. 2, oc., c.) ; above, the arch overlaps the vertebra 
in an imbricated manner (fig. l). 
* Most solid in its cranial , yet the Snake’s skull is, of all others, the most elastic and mobile in its 
facial parts ; no foot must bruise its head, for it is doomed to go on its belly all the days of its life, yet its 
throat must be, practically, “ unhidebound devouring, as it does, prey, whose girth is many times its 
own. 
3 G 
MDCCCLXXVIII. 
