THE VIPERS 



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in the female, of a pair of scale-covered, horn-like processes above the eyes, the 

 arrangement of the scales of the body in oblique rows, and the short keels on the 

 scales, which stop short of their tips. The common horned viper may be immedi- 

 ately recognized as an inhabitant of desert places from the general sombre and 

 mottled tone of its coloration, which is so admirably adapted to such surroundings. 

 Usually attaining a length of about two feet, it is of a light brownish ground color, 

 more or less tinged with yellow, upon which are six longitudinal rows of circular or 

 quadrangular dark markings, increasing in size from the middle of the back toward 

 the sides. Beneath the eyes run a dark brown band, while the middle of the head 

 is marked by a light brownish yellow streak, dividing posteriorly, and uniting on 



HORNED VIPERS IN THE SAND. 

 (One-half natural size.) 



the sides of the neck with another stripe coming from the chin. The scales sur- 

 rounding the mouth are a bright sandy yellow, the shields on the under surface being 

 also either -bright yellow or whitish. The scales of the body are arranged in from 

 twenty-nine to thirty-three rows; the anal shield is single, while the shields 

 beneath the tail form a double series. The range of this snake includes Northern 

 Africa, east of Morocco, as well as Kordofan and Arabia, the second species being 

 likewise North African. Canon Tristram writes that the usual habit of the horned 

 viper is "to coil itself on the'sand, where it basks in the impress of a camel's foot- 



