AGAMIDAE 



521 



cavities of old walls, provided there is vegetation. They require 

 vegetable food, besides insects, grazing on grass, and having a 

 fondness also for Mesembryantliemum cardiforme. Very large 

 males reach a total length of one foot. They are pugnacious, 

 especially during the time of breeding. The male inflates its 

 gular sac into the size of a walnut, stands up upon its four 

 limbs, with its head slightly lowered and turned to one side. 

 Then it darts upon the foe which it has been eyeing for some 

 time. 





FIG. 125. Agama stellio. 



. A. stellio is the commonest Agama in Egypt, Asia Minor, and 

 in some of the Grecian Islands, where the Greeks still call it 

 korkordilos, just as they did in the time of old Herodotus. The 

 Arabic name is kardun. This lizard is easily recognised by the 

 irregular folds on the neck, which are beset with spinous horny 

 scales. It grows to a length of 15 inches. The general 

 colour is brown, with dark patches on the back. When basking 

 they become almost black ; in the breeding season the male 

 assumes red tints on the head and neck. 



Phrynocephalus. This is a typical Agamoid of the steppes 

 and deserts of Asia. The head is short and thick, the ear is 



