COLUBRINE GROUP. 
207 
inhabiting Hungary and the Mediterranean countries, and extending as far north 
as the south of Switzerland; while in the east it is represented by a variety known 
as the Balkan snake, which attains a larger size than the typical form. These 
snakes are distinguished from their allies by the regular arrangement of the shields 
on the head, and the presence of two preorbital shields, of which the lower is small 
and placed in the line of the labials; and they are further characterised by the 
relative shortness of the tail, which scarcely reaches a fourth of the total length. 
The smooth scales are arranged in from seventeen to nineteen rows. The ordinary 
form may attain a length of about 4 feet, but is generally smaller. In ground¬ 
colour the head and nape are greyish yellow, the hack and tail greenish, and the 
under-parts yellow, upon them being black markings, which, while irregular above, 
form regular oblique bars inferiorly, and in the hinder part of the body are 
arranged in longitudinal stripes which continue to the end of the tail. In some 
specimens, however, the ground-colour of the upper-parts is a beautiful yellowish 
green, while on the lower surface it is canary-yellow; in a third variety the whole 
upper surface is uniform olive-brown, and in some cases it is completely black, the 
under surface of the body being grey, with a steely blue lustre on the sides and the 
whole of the under-parts. This snake is very abundant in Italy, and may he met 
with in most gardens in the neighbourhood of Rome. Its habits vary to a certain 
extent according to locality; and while in the Russian steppes it frequents the 
hottest and driest spots, in Dalmatia and the Tyrol it is found in sunny, although 
by no means dry situations, either in woods or among old buildings. 
The other European species is the horseshoe snake (Z. liiwo- 
Horseshoe Snake. _ L 1 x 11 
crepis), common both to Southern Europe and Northern Africa, and 
represented in the lower figure of the illustration on p. 208. From its allies it 
is -distinguished by the presence of a series of small suborbital shields beneath 
the eye, which completely separate it from the upper labials, by the divided 
anal shields, the presence of from twenty-five to twenty-nine longitudinal rows of 
scales on the body, and likewise by the constancy of the coloration. Measuring 
nearly 6 feet in length, this handsome snake has the ground-colour of the upper- 
parts varying from greenish or greyish yellow through orange to reddish brown. 
As a rule, the head is marked by a dark oblique band between the eyes, behind 
which is a second band, convex in front, and reaching to the neck, and a third 
marked with light spots, so that a horseshoe pattern is formed between the spots 
and bands. On the back runs a row of yellow-edged dark oval patches, which 
tend to unite towards the hinder extremity; and on each side of this are a series 
of smaller spots, beneath which, again, are more upright dark marks, extending 
downwards to the lower surface. As the upper dark patches arc very large, the 
ground-colour is generally reduced to a series of rings, forming a very regular and 
pretty pattern. The under-parts are yellow or orange-red, spotted with black. 
Here also must be mentioned the Indian rat-snake (Z. mucosus), 
Rat-Snake. . x n 
now included in this genus, although formerly referred to the next. 
It is a large species, attaining a length of 6 feet or more. In colour it is brown 
above, frequently with more or less distinctly defined black crossbands on the 
hinder-part of the body and tail; the under surface being yellowish, often with 
black edges to the shields of the hinder-part of the body and tail. The range of 
