214 THE VIVARIUM. 
All the Aglyphodont Colubrine Snakes are non-poisonous, and 
are arranged in more than 700 species. It will, therefore, be 
easily seen that this family comprises a very great proportion of 
all Ophidians. 
Representatives of this series are found in every part of the 
temperate, sub-tropical, and tropical regions of the earth. The 
Aglyphodont Colubrine Snakes are arranged by the _ great 
authority just quoted in three sub-families: 1. Acrochordine 
(the Wart Snakes); 2. The Colubrinw (the typical Snakes) ; 3. 
The Rhachiodontine (The Egg-eaters). 
In the first sub-family there are five genera, and in the last 
there is only one genus; but in the second there are as many as 
122. 
The Wart Snakes, which are natives of South Kastern Asia and 
Central America, are of moderate length, and generally have 
their head and body covered with small granular or spiry scales, 
which do not overlap each other, or only slightly so—hence their 
name. These Snakes are mostly rare, aquatic, and viviparous, 
and not suitable for confinement. 
As so many of the members of the very large sub-family 
Colubrine may be kept without difficulty in captivity, only, 
comparatively, a few of them can be described in these articles. 
Mr. Boulenger has divided the Colubrinw into two series, ac- 
cording to the presence or absence of the hypapophyses or hemal 
processes on the posterior dorsal vertebree (see Figs. 57 and 58), 
and the crest or tubercle which projects below. 
The first genus of the Colubrinw to which reference will be 
made is the genus Tropidonotus. This is a very large genus, and 
comprises about seventy-six species. Most of its members have 
keeled scales, hence its name (from Greek tropis, gen. tropidos, 
a keel, and notus, a back). Representatives of the genus are 
found in Kurope, Asia, Africa, North Australia, and North and 
Central America. 
The Green Spotted Garter Snake (Zropidonotus ordinatus), 
Fig. 63, is a native of North America, and lives exceedingly well 
in confinement, where it has sometimes bred, the young being pro- 
duced alive. Chiefly owing to its very variable coloration, there 
are many varieties of this Reptile. When full-grown, it is about 
