136 ANIMAL LIFE OF THE BRITISH ISLES. 



Common Lizard (Lacerta vivipara, Wagl). 



There are still two small groups of back-boned animals to be 

 described, representing the classes Reptilia and Batrachia. To 

 the average man they are all Reptiles, and he has this justifica- 

 tion for so regarding them that until recently they were so 

 classified by the great naturalists. Modern biologists, however, 

 dealing with structure and organisation rather than with external 

 form, find that this association of the scale-clad Lizards and 

 Serpents with the soft-skinned Frogs, Toads, and Newts cannot 

 be defended, and they have separated them into the two classes 

 named. The reasons for this separation will become manifest 

 in our descriptions of the several species, so that a preliminary 

 dissertation on the subject is not necessary. 



Sitting on a sunny, heather-clad hillside it will not be long, 

 probably, before we see the active little Common Lizard peep- 

 ing at us from under cover or leaping swiftly over the crowded 

 plants. Its movements are so rapid that it is not at all easy to 

 follow them in detail, or even to catch one for closer examina- 

 tion; It can run nimbly enough with a gliding motion, for the 

 body and tail are scarcely lifted from the ground ; but the 

 principal mode of progression is to shoot forward horizontally 

 from one tuft of herbage to the next. They run with as much 

 facility over the shoots of heather or heath, and their long, 

 delicate fingers and toes secure them as sure a landing as that 

 of the Squirrel leaping from branch to branch. When we have 

 hit upon a spot where we have seen several Lizards thus active, 

 a good plan is to sit down quietly for a time, and keep our eyes 

 on a patch of sand that is fully exposed to sunshine. In a little 

 while a Lizard, maybe two or three Lizards, will appear from 

 under the heather or other plants and bask in the sun. 



So seen, we note that they are about five inches in length, 

 which is only an average size. The maximum attained by 

 males is six inches, and by females seven inches. The females 



