50 BRITISH LIZARDS 



the pre-anal scales of an adult male of Sceloporus 

 horridus of Mexico. Here the epidermis is greatly 

 thickened above the middle posterior part of the scale, 

 so much so as to make a deep impression in the true 

 skin, simulating a true pre-anal pore. I suspect that 

 the nature of these structures is similar to that of 

 corns in higher Vertebrata." ^ 



The relative size, the colour, and the viviparous 

 character of the common lizard, will be the points 

 that the field naturalist will keep in mind as dis- 

 tinguishing this species from the sand lizard, not 

 forgetting the wide distribution of the former com- 

 pared with the very restricted distribution of the 

 latter. 



Haunts. — It has been noted that, as far as Europe 

 is concerned, this lizard shows a preference for 

 mountainous areas, but in England it will be found 

 in flat districts as well as hilly. My own experience 

 has been to see more specimens in dry sandy spots 

 than in well-watered and greener places. Moors and 

 commons and heaths seem to be its haunts particu- 

 larly, as well as sandhills near the coast. I took 

 half a dozen of these lizards one morning on the sand- 

 heaps on the coast of Norfolk, near Stalham, where 

 they scuttled across the sand from one stunted bush 

 to another, or into tussocks of grass. I also saw a 

 good many on a gorse-covered common in Dorset, so 

 that they are not very particular as to the kind of 



^ Cope, Crocodiles, Lizards, and Snakes, p. 198. 



