46 MONITORS. LIZARDS. 



21. The GAVIALS differ from the two preceding genera in 

 their very long slender muzzle, as well as in their teeth, which 

 are nearly equal. They are only met with on the eastern con- 

 tinent. The most common is the Gavial of the Ganges, 

 Lacerta gangetica, which is said to attain thirty feet in length, 

 but is not dangerous either to man or large animals ; it feeds 

 exclusively on fishes. 



FAMILY OF LACERTIANS. 



22. The Lacertians have five distinct toes on all their feet, 

 armed with nails; the tongue is thin, extensile and terminated by 

 two threads : their scales are arranged in transverse and parallel 

 bands around the tail, and under the belly, some have teeth in 

 the jaws only, and others have them also in the palate. The first 

 form the tribe of Monitors, and the second that of Lizards. 



23. The MONITORS generally have a laterally compressed tail, 

 like that of the Crocodile. Monitors properly so called are 

 recognised by the small scales that cover the head, limbs and 

 whole body. Two species are found in Egypt : one, the Monitor 

 of the ]\ile, Lacerta nilotica, is five or six feet long, and is 

 seen sculptured on the monuments of the ancient Egyptians ; 

 the other, called the Land Monitor of Egypt, on account of its 

 terrestrial habits, is common in the deserts, in the vicinity of that 

 country. 



24. Other Monitors, called Sauvegardes, have the top of the 

 head furnished with angular plates ; and the belly and tail are 

 covered with large rectangular scales. 



25. The TRIBE OF LIZARDS, is composed of Lizards properly 

 so called, and some similar genera, in which the palate is armed 

 with two rows of teeth, and the tail is cylindrical. Most of them 

 are also distinguished by a sort of collar, placed under the neck 

 and formed of a transverse range of large scales, separated from 

 those of the chest, by a space covered only by granulations. In 

 general, they have also, under each thigh, a longitudinal series of 

 projecting pores, and the whole top of the head is armed with a 

 bony shield, which is covered by large horny plates. 



26. LIZARDS PROPERLY so CALLED, Lacerta, have the top of 

 the body covered by small scales similar to granulations, while 

 beneath the belly they have large transverse plates. These 



21. How do Gavials differ from other Crocodiles ? 



22. What are the general characters of the Lacertians? 



23. How are Monitors recognised ? 



24. What are Sanvegardes ? 



25. What are the general characters of the tribe of Lizards ? 



26. How are Lizards properly so called characterised ? What are their 

 habits ? Upon what do they feed ? Are they poisonous ? 



