COLUBRINE GROUP. 
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dots and a chestnut-brown spot on the shields of the head, while the neck has a large 
blackish or reddish brown patch, and rows of smaller spots of the same colour 
ornament the back. There is also a dark band from the eye to the corner of the 
mouth; each side of the body has a row of small spots; and the under-parts are 
whitish with a brown marbling. The cat-snake ranges from the shores of the 
Adriatic to the neighbourhood of the Black and Caspian Seas, and Africa as far south 
as 45° N. It inhabits rocky and sunny spots, and feeds mainly if not exclusively 
on lizards. Although slower than the water-snakes, its movements are more rapid 
than those of the vipers. The virulence of its poison is shown by tl\e circumstance 
that a lizard bitten by one of these snakes died in a minute and a half. 
Nocturnal Tree- The tropical regions of the Old World are the home of the typical 
Snakes. genus ( Dipsas ) of the subfamily, which is characterised by the 
long and compressed body and tail, the sharp distinction of the head from the neck, 
the moderate or large size of the eye, with its vertical pupil, and the normal 
arrangement of the shields on the head, in which the hinder nasal is more or less 
markedly hollowed. The number of teeth in the hinder upper jawbone varies from 
ten to twelve, the two or three hinder pair being elongated and grooved; while in 
the lower jaw the front teeth are the largest. The scales on the body are arranged 
in from seventeen to twenty-seven longitudinal rows, those of the middle row of 
the back being larger than the rest; and the medium-sized or long tail has its inferior 
shields in two rows. These snakes are represented by about twenty species, 
inhabiting Southern Asia, New Guinea, Northern Asia, and Africa. The majority 
are inhabitants of forests or scrub-jungle, and are almost entirely arboreal; but a 
few are terrestrial, and frequent open country. Many of these snakes attain a 
length of 6 or 7 feet, and their prevalent ground-colours are brown and black. 
The Indian forms at least are purely nocturnal, and their food consists of mammals, 
birds, and, more rarely, lizards, and occasionally birds’ eggs. It is noteworthy that 
some species prey entirely on mammals, while others confine their attention to 
birds. Eight species of the genus are recorded from India, Ceylon, and Burma; 
while a well-known Malayan form is the ularburong (Dipsas dendrophila). 
Back-Fanged These snakes are represented by two important genera, of which 
Tree-Snakes. Philodryas is mainly characteristic of the tropical parts of America, 
although it also occurs in the West Indies and Madagascar; while the whip-snakes 
(Dryophis) are confined to India and the Malay countries. In the American genus 
the hinder fangs are not very large, being not double the height of the solid teeth 
in front of them. The body and tail are elongated and more or less compressed, 
the eyes large, and the smooth or keeled scales arranged in from seventeen to 
twenty-one rows; while the prevailing colour is green. The genus is represented 
by some fifteen species, among which the green snake (P. viridissimus) is a well- 
known form. This species attains a length of nearly three feet, and has upwards 
of two hundred shields on the lower surface of the body. 
In the Indian whip-snakes the teeth in the posterior upper jawbone vary in 
number from twelve to fifteen, one or two near the middle being much enlarged 
and fang-like. After these comes an interval devoid of teeth, and at the hinder- 
end of the jaw the two last teeth are grooved. In the lower jaw the third or 
fourth tooth is enlarged and fang-like; those in the hinder-part of the series being 
