MANUAL OF NATURAL HISTORY. 57 



generative organs bifid ; oviparous, rarely ovovivipa- 

 rous ; eggs when deposited with a more or less co- 

 riaceous shell. 



I. ORDER — Lizards (Sauria). 

 Mouth not dilatable ; jaws toothed ; lower jaw- 

 bones united in front by a bony suture ; eyes gene- 

 rally with distinct eyelids ; drum of ear generally 

 distinct, exposed ; limbs 4, distinct, rarely rudimen- 

 tary ; toes clawed ; body elongate, rounded, co- 

 vered with imbricated or granular scales ; tail elon- 

 gate, tapering, rarely prehensile, generally covered 

 with whorls of scales ; eggs with hard skin. 



I. SUB-ORDER. — Slender-tongued Lizards 

 (Leptoglossata). 

 Tongue flat, elongate, and bifid. 



1. TRIBE. — Cyclosaurians (Cyclosauria). 

 Scales of belly square, in cross bands; of back and 

 tail rhombic and imbricate, or circular and sub-gra- 

 nular, in cross-rings ; of sides generally granular ; 

 tongue elongate, flattened, base sometimes sheathed, 

 generally free, with two elongate, cylindrical, horny 

 tips ; tail elongate, with whorls of scales, generally 

 conical, tapering, sometimes compressed, with two 

 elevated crests above. 



A. Head with small many-sided shields. Tongue 



sheathed at base. Sides Jiattish, granular. 

 1. Family. — Monitors (Monitoridae). Head-shields 

 minute, flattish, polygonal ; tongue retrac- 

 tile ; scales small, roundish, in cross rings, 



d 5 



