430 SNAKES. 
scarcely be distinguished from them. A detailed account of this specimen is 
given in my “ Glimpses into Petland,” published by Messrs. Bell and Daldy. 
The young of the Chameleon are produced from eggs, which are very 
spherical, white in colour, and 
(Ye, covered with a chalky and very 
VY fp (> porous shell. They are placed on 
=] fase the ground under leaves, and 
.. there left to hatch by the heat of 
\" the sun and the warmth produced 
by the decomposition of the leaves. 
The two sexes can be distinguished 
from each other by the shape of the 
tail, which in the male is thick and 
iS swollen at the base. 
‘ 
THE large and important order 
at which we now arrive consists of 
reptiles which are popularly known 
as SNAKES, or more scientifically 
as Ophidia, and to which all the true Serpents are to be referred. 
The movements of the Serpent tribe are performed without the aid of 
limbs, and are, as a general rule, achieved by means of the ribs and the 
large curved scales that cover the lower surface. Each of these scales over- 
laps its successor, leaving a bold horny ridge whenever it is partially erected 
by the action of the muscles. The reader will easily see that a reptile so 
constructed can move with some rapidity by successively thrusting each scale 
a little forward, hitching the projecting edge on any rough substance, and 
drawing itself forward until it can repeat the process with the next scale. 
The movements are consequently very quiet and gliding, and the creature is 
able to pursue its way under circumstances of consideratle difficulty. 
The tongue of the Snake is long, black, and deeply forked at its extremity, 
and when at rest is drawn into a sheath in the lower jaw. In these days 
it is perhaps hardly necessary to state that the tongue is perfectly harmless, 
even in a poisonous serpent, and that the popular idea of the “sting” is 
entirely erronzous. The Snakes all seem to employ the tongue largely as 
a feeler, and may be seen to touch gently with the forked extremities the 
objects over which they are about to crawl, or which they desire to examine. 
The external organs of hearing are absent. - 
' The vertebral column is most wonderfully formed, and is constructed with 
a special view to the peculiar movements of the serpent tribe. Each 
vertebra is rather elongated, and is furnished at one end with a ball and at the 
other with a corresponding socket, into which the ball of the succeeding 
vetebra exactly fits, thus enabling the creature to writhe and twine in all 
directions without danger of dislocating its spine. This ball and-socket 
principle extends even to the ribs, which are jointed to certain rounded 
projections of the vertebrae in a manner almost identical with the articu- 
lation of the vertebrze upon each other, and, as they are moved by very 
powerful muscles, perform most important functions in the economy of the 
creature to which they belong. 
The bones of the jaws are very loosely constructed, their different portions 
being separable, and giving way while the creature exerts its wonderful powers 
of swallowing. The great python Snakes are well known to swallow animals 
of great proportionate size, and anyone may witnzss the singular process by 
taking a common field snake, keeping it without food for a month or so, and 
then giving it a large frog. As it seizes its prey, the idea of getting so stout 
CHAMELEON.—(Chameleo vulgaris.) 
