Markings on the Top of the Head. 



Even though the var 

 the head is very great, 

 and the amount of slmpll 

 two large groups: 1) a 



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Z)Ub 



A 



4 







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lability of the pattern on the top of 

 depending on the [pattern's] shape 



flcatlon, It Is possible to recognise 

 pattern with one transverse element 

 (like the tip of a spear - Fig. 

 2a) and Its modifications which 

 relate to the reduction of the 

 sides of the pattern and 

 convert the pattern into either 

 a broad cross (Fig. 2b) or a 

 narrow cross (Fig. 2c); 2) a 

 pattern with two transverse 

 elements forms as a result of 

 the reduction of the sides and 

 the middle part of the tip of 

 the spear; sometimes it divides 

 vertically into two (Fig. 2d) 

 sometimes it becomes 

 indiscernible. 



^ 



Fig. 2. The pattern on the top of the head. 

 Modifications of the pattern with one 

 transverse element, a - tip of a spear, b - 

 broad cross, c - narrow cross; d 

 modifications of the pattern with two 

 transverse elements. 



Paleoaslatic vipers have the pattern of the first group 

 with modifications mainly towards a narrow cross. Indian 

 vipers also have the pattern of the first group but with 

 modifications mainly towards a broad cross; all African 

 vipers have the pattern of the second group. 



