1 142 CLASS REPTILIA. 



the vertebrae are three times the size of those of V. sivalensz's, and the 

 total length did not probably fall short of thirty feet. This species was 

 originally described by Sir R. Owen under the name of Megalania ; cer- 

 tain remains which were referred to it having subsequently proved to 

 be Chelonian. An imperfectly known species, from the Lower Pliocene 

 of Attica, may perhaps belong to the former group. 



It may be well to mention here that Sir R. Owen has described 

 two peculiar blunt and pleurodont teeth of a large lizard from the 

 Pleistocene of Queensland under the name of Notiosaurus, which 

 is, however, preoccupied by the genus Notosaurus (p. 1139). It is 

 just possible that these teeth may be referable to Varanus firiscus, 

 in which event the generic term Megalania would have to be re- 

 tained for that form. 



Family Teiid^e. — In this family, which is confined to America, 

 the supratemporal fossae of the skull are not roofed over, the denti- 

 tion is pleurodont or subacrodont ; the teeth, although variable in 

 form, are always solid at the base ; and there are no dermal scutes. 

 An existing species of Tupinambis is represented in the Pleistocene 

 cave-deposits of Brazil. 



Family LacertiDjE. — In the LacertidcE the supratemporal fossae 

 are roofed over by bone ; the premaxillae are united ; the dentition 

 is pleurodont, the bases of the teeth being hollow ; and there are no 

 dermal scutes. All the genera belong to the Old World. Remains 

 of the existing Lacerta ocellata occur in the Pleistocene of France, 

 and extinct species referred to the same genus have been described 

 from the Miocene and the Upper Eocene Phosphorites of the same 

 country. 



Family Scincid/e. — The Scincoid Lizards form a large cosmo- 

 politan family, characterised by the bony scutes roofing over the 

 supratemporal fossae ; the separate or imperfectly united premaxillae ; 

 the pleurodont dentition ; and the presence of dermal scutes. Dra- 

 ccenosazirus, of the Lower Miocene of France, is an extinct genus 

 with molariform teeth, probably allied to the existing Scincus (fig. 

 1 041) or Chalcides. 



Suborder 2. Rhiptoglossa. — The Chatneleontidce, or Chame- 

 leons, differ from the Lacertilia in that the nasals do not enter into 

 the borders of the nares ; the pterygoid does not articulate with the 

 quadrate ; and, although limbs are present, there are no clavicles or 

 interclavicle. The dentition is acrodont. All the existing forms 

 are Old World ; but Dr Leidy has described part of a mandible 

 from the Upper (Bridger) Eocene of Wyoming, which he refers to 

 the type genus Chameleon. 



Suborder 3. Dolichosauria. — This group was originally formed 

 for the reception of the genus Dolichosaurus, from the English 

 Chalk • which is a small snake-like Lizard, with more than nine 



