24 VENOMS 



elongate pupils, separated from the labials by scales ; nostrils 

 lateral. Body cylindrical. Scales keel-shaped, with an apical pit, 

 in from 19—31 rows ; ventral scales rounded. Tail short ; sub- 

 caudal scales in two rows. 



The Genus Vipera is represented in Europe by several species, 

 which are likewise found in Western Asia and North Africa. 



These species are : — 



V. ursinii, V. herns, V. aspis, V. latastii, and V. ammodytes} 



Yipera ursinii. 



Snout obtuse, soft on its upper surface, with the frontal and 

 parietal shields distinct, the former about one and a half times 

 as long as broad, and almost always longer than the parietals. 

 A single series of scales between the eyes and the free margin of 

 the lips. 



Temporal shields smooth. Body scales in from 19 to 21 rows, 

 strongly keeled on the back, less strongly on the sides. 



Colour yellowish or pale brown above, grey or dark brown on the 

 sides, sometimes uniform brown ; spots more or less regular on the 

 vertebral column, oval, elliptic or rhomboidal, dark brown or flecked 

 with white, sometimes forming an undulous or zigzag band ; two or 

 three longitudinal series of dark brown or black spots on the sides ; 

 small dark dots running obliquely from the eye to the angle of the 

 mouth ; nose and lips white, and one or two dark angular streaks 

 on the head ; chin and throat yellowish ; belly black, with trans- 

 verse series of white or grey dots. No sexual differences in 

 coloration. 



Total length from 420—500 millimetres; tail 50— .55. 



' As regards the distinctive characters of these various snakes, and of the 

 majority of those that we shall describe in this book, we have followed the state- 

 ments in the " Catalogue of the Snakes in the British Museum (Natural History)," 

 vol. iii., by George Albert Boulenger, F.B.S. (London : Printed by order of the 

 Trustees, 1896.) 



