HISTORY AND DISTRIBUTION. 13 
strata below the Cretaceous we find no traces of fossil snakes, 
so we naturally conclude snakes were evolved from reptiles with 
legs about this period, or Epoch, in the history of the Earth. 
From Cretaceous times up to the present, snakes have evi- 
dently been on the increase, not only in numbers, but species 
judging by the comparatively few fossil snakes found. There 
are at present about 1500 species or kinds of snakes scattered 
over all the countries of the world, with the exception of New 
Zealand, where they have never been known to exist. Snakes 
are most abundant in the tropical and semi-tropical portions of 
the globe, in districts where forests and rank vegetation abound, 
for it is there they find an abundance of food and suitable shelter, 
as well as the necessary warmth to quicken their sluggish vital 
forces. 
Extinct species of snakes of the Cobra family have been found 
in the Lower Miocene in Germany. Others of non-venomous 
species have also been discovered in the same formation. In 
Turkey and America fossil remains of snakes of the Crotaline 
sub-family have been unearthed. 
SNAKES AND LIZARDS. 
In outward appearance the limbless lizards resemble snakes 
in possessing tapering snake-like bodies, and being destitute of 
legs. Nobody would mistake a lizard with legs for a snake, 
but to those people who have not made a study of the anatomy 
of snakes and lizards, those lizards which are destitute of legs are 
invariably mistaken for snakes. 
The general appearance of any ordinary snake is such that 
any one of average intelligence will immediately recognize it as 
a snake. There are, however, families of snakes known as the 
Typhlopiude and Glauconiide, which are very worm-like in 
appearance, and might easily be mistaken for legless lizards or 
worms. In fact, the older naturalists classified them as lizards. 
Snakes differ from lizards in the following ways :— 
(1) The two parts of the lower jaw are attached in front by 
elastic ligaments, permitting the separation of the two halves of 
the lower jaw, for the purpose of permitting large prey to be 
swallowed. In the lizards these bones are solidly united in 
front. 
