554 



ORDER III. SAUBIA. 



491. THE number of species included in this order is very 

 considerable ; and their variation in form, dimensions, and cha- 

 racter, is far greater than is to be met with in the preceding 

 groups. The contrast is still more striking when we include in 

 our survey those fossil remains of Saurian Reptiles which abound 

 in many parts of the world ; for great as may be the difference 

 in size and appearance between many of the existing Lizards, it 

 sinks into nothing in comparison with that between any living 

 forms and the monstrous Saurians of the ancient marshes and 

 waters, or the Pterodactyles, which are supposed to have winged 

 their Bat-like way through the air. The diversity in the habits 

 of the existing Saurians is very considerable ; a few are more or 

 less aquatic ; others strictly terrestrial, living on the ground, and 

 retreating for shelter to holes burrowed beneath the surface ; 

 whilst others are entirely arboreal, passing their whole lives 

 amongst the branches of trees. They mostly feed on animal 

 substances ; some preferring flesh, and others devouring insects 

 and worms ; one family is almost exclusively herbivorous. They 

 are all furnished with teeth, which are of a simple conical form, 

 and adapted rather for securing and tearing their food than for 

 masticating it. The principal families included in this order 

 are the following: 1. CIIAM^LEONID^E, or Chameleons ; 2. GEC- 

 KOTiDvE, or Geckos ; 3. IGUANIDJS, or Iguanas; - 4. AGAMID^E, 

 or Agamas; 5. VARANID^E, or Monitors; 6. AMEIVID^E, or 

 Tejuexins ; 7. LACERTID^E, or True Lizards ; 8. CHALCID^E, 

 or Snake-Lizards ; 9. SCINCID^E, or Skinks ; and 10. GYM- 

 NOPHTHALMID^E, or Naked-eyed Lizards. The first four of these 

 families have the tongue thick and fleshy, whence they are called 

 Pachyglossa, or Thick-tongued Lizards ; in the remainder, this 

 organ is slender, bifid, sheathed, and capable of being protruded 

 without the mouth being opened ; these are called Leptoglossa, 

 or Slender-tongued. Besides the above families there are two 

 which appear to unite the Lizards with the Snakes, and which 



