COLUBRINE GROUP. 
2I 5 
by hunger descend to the ground and rob hens’ nests. That such a tiny creature 
should be able to swallow a hen’s egg seems incredible, but nevertheless a specimen 
has been taken with the egg actually within its jaws, and the whole head so 
swollen as to render the mouth incapable of being closed; while an example 
in the London Zoological Gardens swallowed pigeons’ eggs without any aj>parent 
difficulty. When swallowed, the egg is split longitudinally by the row of teeth in 
the throat, and the whole of the contents secured. After being thus broken, the 
two halves of the shell, generally fitted into one another, are rejected. 
The pale snakes, or, as they are called in Brazil, the moon-snakes. 
Moon-Snakes. r J . ’ 5 
may be taken as our first representatives of the second of the three 
great parallel series into which the Colubrine family is divided. This back-fanged 
series, or Opisthoglossa, is characterised by having one or more pairs of the hinder 
CROWNED MOON-SNAKE (§ nat. size). 
upper teeth longitudinally grooved, and thus capable of acting as poison-fangs. 
Many of these snakes are indeed extremely venomous, their bite being capable of 
producing death in a few minutes. They are divided into two subfamilies, of which 
the first, or Dipsadince, are characterised by the lateral position of the nostrils; 
and they are either terrestrial or arboreal in their habits, while their distribution 
is world-wide. 
Belonoino- to the first of the two subfamilies, the moon-snakes are characterised 
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by the slender and somewhat compressed form of the body; the flattened head, 
which is but imperfectly differentiated from the neck, is broad behind and narrow 
in front, although somewhat pointed at the muzzle; while the upper jaw projects 
considerably over the lower. The scales, moreover, are smooth; both the anal 
shield, and the shields on the lower surface of the tail are single; and the eye, 
as in most of the other members of the subfamily, has the pupil vertical. The 
