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SNAKES. 
Somewhat superior in size to the common viper, this species {A. 
Siberian Haiys. ma y b e recognised by the small portion of the head that is 
covered with shields, and also in that each shield, or pair of shields, overlaps with 
its hinder edge the shield immediately behind it, thus producing a more or less 
marked imbrication of the whole of the head-shields. Another characteristic is to be 
found in the small size of the anterior frontal shields, which together have a crescentic 
shape and a somewhat saddle-shaped upper surface. The head is very distinctly 
defined from the compressed neck, the body being rather long, of a rounded trian¬ 
gular form in the middle, and covered with twenty-three rows of triangular scales; 
the very short tail, which is much thinner than the hinder-part of the body, is 
conical, and armed at the extremity with a forked horny appendage. The ground- 
siberian halys viper (| nat. size). 
colour of the middle of the back is a dark brownish yellow grey, while that of the 
under-parts is a yellowish white, with more or less well-defined black spots on the 
hinder shields. The yellow ground of the labial shields of the head has chestnut- 
brown markings; and the crown of the head bears a large quadrangular blotch, 
forming an interrupted transverse band on the frontal shields, and a temporal band 
running from the hinder border of the eye to the angle of the mouth and the side 
of the neck. Somewhat similar markings ornament the back, and are more or less 
clearly margined with yellow. Along the whole length of the back and the ridge 
of the tail are a number of yellowish or yellowish white black-edged irregular 
blotches or crossbands; and on the sides are two rows of blackish brown spots 
with white edges, which frequently run one into another, the first dark spot on 
the neck differing from the rest by its horse-shoe form. The distributional area of 
this snake extends eastwards from the Volga to the Yenesei. In Europe the halys 
