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is covered with scutes, the rest of the body with scales, those of the 

 breast and belly being distinguished by their larger size and brighter 

 colour. The latter, however, does not betray the animal's presence, as 

 the scales in running are in contact with the ground. In the course of 

 the summer the skin with the scales is peeled off several times in shreds 

 by rubbing against stones, stalks, etc. Its inconspicuous colour forms 

 an excellent protection to the animal against 



D. Its Enemies. 



Among these we must place the smooth snake, the viper, the marten, 

 falcons, crows, shrikes, etc. Against these this feeble animal is unable 

 to defend itself, and its only escape lies in great caution and speedy flight 

 (see Section E, 1 and 2). 



E. Food. 



The lizard is a predaceous animal. Its food consists of butterflies, 

 moths, beetles, grasshoppers, crickets, flies, all kinds of insect larvae, 

 spiders, earth-worms, and small slugs. 



I. The animal has acute senses. Its ear can detect the lightest 

 rustle. The tympanic membrane is freely exposed and visible at the 

 back of the head in the form of a small dark spot. The eyes are brilliant, 

 and, as in birds, furnished with two eyelids and a nictitating membrane. 

 The animal only takes notice of moving prey. The tongue is long, deeply 

 forked at its end, and protrusible. It serves as an organ of touch, and 

 y by its aid also the animal drinks, for which pur- 

 pose the tongue is moistened with dew or dipped 

 into the water, and then drawn back into the 

 mouth. 



2. Movements. (a) The lizard runs along the 

 ground in jerks, rapidly and nimbly. The legs 

 are short, weak, and directed laterally away from 

 the body. By their aid alone the animal cannot 

 execute its rapid forward movements. These, in 

 fact, are accomplished by undulating movements 

 of the whole body, the lower surface of which 

 touches the ground. Let us assume the body to 

 be stretched to its full length, as shown in line 1 

 - of accompanying diagram (Y represents the posi- 

 tion of the fore, H of the hind, limbs). If while 

 the fore-limbs remain fixed the body is bent towards the side, the hind- 

 limbs will be drawn further forwards, as shown in line 2. If now the 



