92 ANNALS OF SCOTTISH NATURAL HISTORY 



THE SERPENTS OF SCOTLAND AND 

 THEIR STUDY. 



By GERALD LEIGHTON, M.D. 



I AM inclined to think that the Order Ophidia or Serpents 

 is not a popular subject of study with Scottish field 

 naturalists. I have several reasons for that belief, one being 

 that any reference to this branch of the fauna in the 

 " Annals " is a somewhat rare occurrence ; another being 

 that I have found it a matter of the greatest difficulty to 

 obtain reliable information about the Order in Scotland. 

 I do not think one need look very far to account for this ; 

 it is doubtless due to the fact that the sole Scottish repre- 

 sentative of the Order of Serpents is a venomous species, 

 viz. Vipera bems, the Adder or Viper, and to the corollary 

 of that fact which 1 think will be undisputed -that ex- 

 tremely few field naturalists care about having anything 

 more than a passing acquaintance with venomous reptiles. 

 This explanation brings me at once to the point of this 

 paper, which is, that of the Distribution of the Order 

 Ophidia with special reference to Scotland. 



The distribution of snakes in the British Isles is a very 

 interesting one, and in order to appreciate the position of 

 Scotland we must notice that of the other parts of the 

 area. More than that, it is necessary to make some attempt 

 to account for the occurrence of serpents at all in the British 

 Isles, and for their absence in some restricted parts. 

 There are some hundreds of species of existing serpents in 

 various parts of the world, but of these three only are found 

 indigenous in the British Isles, and these three are confined 

 to England, Wales, and Scotland, there being no snakes in 

 Ireland, where the Class Reptilia is represented only by the 

 Order Lacertilia, or Lizards. A few miles away on the 

 Continental side of the British Channel some thirty species 

 of serpents are found. Is it possible, then, to throw any 

 light on the very restricted distribution of this Order in 

 these Isles? Without in any way wishing to be dogmatic, 

 probably some such reasoning as the following must be held 



