212 
SNAKES. 
sides likewise spotted, and the under-parts with a blackish steel-grey tinge. The 
distinctive specific characters are the presence of a small preorbital shield on the 
head; the arrangement of the scales of the middle of the body in from twenty-three 
to twenty-five longitudinal rows—these scales being smooth in the young but 
strongly keeled in the adult—and the divided anal shield. The distributional area of 
this snake includes the whole of Southern and South-Eastern Europe, from Lower 
Italy and Dalmatia to Turkey, as well as Greece and the adjacent islands, and extends 
to the interior of Asia Minor; but there is some doubt whether the species occurs 
in the Caucasian region. All observers are in accord that the four-rayed snake 
FOUR-RAYED SNAKE (J nat. size). 
is not only harmless but useful, since it destroys rats, mice, voles, and smaller 
snakes. It also preys upon moles, lizards, and small birds. 
Black-Marked Another European species of the family is the black-marked 
snake. snake (Coluber scalaris), which belongs to a separate group charac¬ 
terised by the following features. The rostral shield of the head is of a large size, 
convex, and pointed in front, while it extends backwards between the prefrontal 
shields, where it terminates in a point. The tail is relatively shorter than in the 
typical group. The black-marked snake, formerly separated as Rhinechis, 
and represented in the upper figure of the illustration on p. 208 has the 
cylindrical body relatively thick, the tail short and blunted, and the flattened head 
broad behind and sharp in front. The body-scales, which are arranged in from 
twenty-five to twenty-nine rows, are long, four-sided, and smooth; the shields on 
the under surface of the body are bent at the edges; while those beneath the tail form 
a double series. As regards colour, there is much variation; the ground-colour 
varying from bright grey or greenish grey, through reddish or yellowish brown, to 
olive or reddish yellow; while the markings of the head often take the form of a 
