76 THE STORY OF REPTILE LIFE. 



extremely specialised condition, the Lizards 

 among Reptiles occupy the place of the Passeres 

 among Birds. 



Of the senses the best developed is sight, and 

 after this hearing. The majority of species are 

 carnivorous, the larger kinds feeding on small 

 mammals, birds, and the members of their own 

 tribe ; the smaller kinds mainly upon insects, 

 worms, and so forth : a few are exclusively herbi- 

 vorous. Some species of lizards never drink, 

 others do so by lapping movements of the tongue, 

 which varies greatly both in its length, shape, 

 and power of movement. 



Lizards are found over the whole globe, save 

 only polar and sub-polar regions. They may be 

 found in the most arid deserts, as well as the 

 most fertile spots, and extend their range verti- 

 cally to the regions of perpetual snow. But 

 whilst the colder regions afford little more than 

 a bare existence, the tropics and sub-tropical 

 regions produce food in abundance. Consequently 

 it is here that the greatest wealth in point of 

 numbers, size, shape, and coloration is met 

 with. These are the regions wherein the group 

 has attained its maximum development. Escape 

 from the extremes of climate appears to be 

 necessary in all cases, since in tropical climates, 

 during the hottest months of the year, when 

 drought prevails, the bulk of the species fall into 

 a state of torpor; whilst in the colder regions 

 the species hybernate, remaining dormant for 

 many months. 



The evolution of the Lizard tribe has been 

 marked, as we have already hinted, by a very 



