Fig. 3, Geographical distribution of species of snakes of 



the genus Echis ; I - _E_. mu I tisquama tus , 2 - E . 



s ochurek i , 3. - E^. colora tus , 4 - E^. carina tus , 5 - 



E^. pyramidum , 6 - E^. oce 1 la tus , ^ " ^» leucogas ter . 



It must be strongly emphasized that the characters 

 recognized above are less variable in comparison to others - 

 for instance, the ventral scale count, pattern on the body, 

 etc.- and that the character complex of each taxonomic group 

 in each zoogeograhic region is stable. For example, the 

 Paleoasiatic vipers have the same number of midbody scale 

 rows (more than 31), the same throat scale pattern, and the 

 head pattern is of the tip of a spear or its modifications in 

 the direction of a narrow cross. Sometimes the pattern on 

 the head may be completly reduced (E^. colora tus ) . 



The Indian and African vipers possess to a different 

 degree enlarged scales on the back of throat and the number 

 of the small midbody scale rows is less than 31; these groups 

 differ in the pattern on the head - the Indian vipers have 

 the pattern of the tip of the spear or its modification in 

 the direction of a broad cross, whereas the African vipers 

 have the pattern with two transverse elements or it may be 

 reduced completely. 



The facts stated above make it possible to suggest that 

 the vipers found in different zoogeographica 1 regions differ 

 much more from one another than the vipers within each 

 zoogeographic region differ amongst themselves. This 

 statement in turn has an important implication: since it has 

 been shown beyond doubt that there are independent species 

 among vipers within the same zoogeographic regions, vipers in 

 different regions cannot belong to one species. In this 

 case, the presence of hybrids between vipers from different 



