LIZARDS 57 



a broad membrane with rounded outline ; the body and 

 limbs are bordered by strongly denticulated folds. The 

 digits are very strongly dilated, their power of adhesion 

 being so great that once the lizard has fastened itself to 

 an object it is often almost impossible to remove it. 



The members of the Australian and Papuan family 

 Pygopodid^ are snake-like in appearance, being entirely 

 devoid of fore limbs, while the hinder ones are absent or 

 merely represented by scaly flaps, under which the digits 

 are hidden. The exact position of this family in the 

 system is rather dubious, as, although the structure of 

 the skull approaches that of the Geckos, there are many 

 anatomical differences. The eyes, the pupil of which is 

 vertical, are, as in the majority of Geckos, devoid of lids. 



The family is represented by six genera, of which the 

 uniform slate-coloured Pygopus lepidopus, attaining a 

 length of two feet, is the commonest species. 



The Old World lizards of the family Agamid^ are 

 characterized by their acrodont dentition. The limbs and 

 eyelids are well developed. The tongue is thick, entirely 

 attached, or but slightly free in front. The tail, which 

 may be exceedingly long, is not fragile, and is prehensile 

 only in the genus Cophotis. In a number of species 

 ornamental appendages, such as crests and gular pouches, 

 are present, sometimes in the males only, sometimes in 

 both sexes. The shape of the body and the scaling varies 

 according to the modes of life adopted by the genera, and 

 although, generally speaking, the ground Agamids have the 

 body depressed, and the arboreal species compressed, there 



