56 BRITISH LIZARDS 



actually the case. A careful examination of the two 

 species together will render the distinctions quite 

 obvious ; but a large number of field naturalists never 

 see a sand lizard, owing to its limited distribution, 

 and hence are Hable, on encountering an unfamiliar 

 colour variation in the common lizard, to erroneously 

 put the specimen down as Lacerta agilis. The distri- 

 bution of the sand lizard in this country is practically 

 that of the smooth snake (Coronella mistriaca), namely, 

 restricted localities in Dorset, Hants, and Surrey, 

 rarely anywhere else. 



The sand lizard is not very rare on some Dorset 

 heaths, being found especially in the neighbourhood 

 of Poole. It is perhaps as common in parts of Surrey, 

 but is everywhere very local in its distribution. It 

 has been stated to occur in Berkshire, but the evidence 

 is not good, though it is very interesting to remember 

 that twenty years ago the smooth snake (C. austriaca) 

 was also found in that county, where it has recently 

 reappeared.^ When we consider the close connection 

 between these two reptiles, it is just possible that 

 L. agilis once inhabited Berkshire, and that the same 

 causes which led to the extermination of its enemy, 

 the smooth snake, also had an influence in its own 

 distribution. At any rate, it is not found there 

 to-day. Coming to other counties, this species has 

 often been recorded in places where there is no doubt 



^ ** Reappearance of the Smooth Snake in Berkshire," The Field 

 Naturalist's Quarterly, August 1903. 



