524 



LACERTAE 



cross-bands, and with a broad black band reaching from the eye 

 to the shoulder. The under parts are pale olive, with small black 

 dots. The throat, although devoid of a special sac, is frequently 

 bulged out by the hyoid apparatus, as shown in Fig. 127, taken 

 from a specimen in the Zoological Gardens in London. 



Uromastix is a typical desert-form, inhabiting the dry and 

 sandy tracts of North Africa, Arabia, Syria, Persia, and North- 

 Western India. The genus is easily recognised by the short and 

 thick tail, which is covered with whorls of large spinous scales, 

 while the much-depressed body and head are almost smooth, being 



FIG. 127. Physignathus lesueuri. x \. 



covered with very small scales. The tympanum of the ear is 

 quite exposed. The incisors are large, uniting in the adult into 

 one or two pairs of large cutting teeth, separated from the molars 

 by a toothless space. There is a transverse fold on the throat. 

 Pre-anal and femoral pores are well developed. 



These " Spiny-tailed Lizards " live chiefly upon vegetable food, 

 leaves, grass and fruit, but they vary this diet with insects, at 

 least in captivity, where they become rather partial to meal- 

 worms. They are absolutely terrestrial and diurnal, preferring 

 sandy places, where they bask or rather roast themselves in the 

 sun ; for the night, at the approach of rain, or on dull and 

 chilly days, they retire into their burrows, which they dig in 



