774 



COMPENDIUM OF GENERIC DISTINCTIONS. 



Genus. YACARE. Jaws with ridge across face. Hind 

 feet little webbed. Nostrils separated by division of gristly 

 iubstance. Eyelids fleshy. New World. 



Genus. ALLIGATOR. Jaws with small longitudinal ridge 

 between eyes. Hind feet fully webbed. Nostrils separated 

 by division of bony substance. New World. 



Order. AMPHISBJENIA Body long and cylindrical ; 

 covered with squared plates imbedded in the skin, and 

 arranged in cross rows. Limbs either wanting or very 

 feeble. Jaws with teeth. 



Family. AMPHISB.ffilNID.ZE. Teeth on inner side of 

 jaws. Limbs wanting. Body and chest with similar square 

 shields. Pores before vent distinct. 



Genus. AMPHISBJENA. Head flattened, muzzle round, 

 rostral shield triangular and erect. Two shields of nose 

 large, square, and extending across muzzle. Brazil and 

 West Indies. 



Family. CHEIROTIDJE. Teeth conical, curved back- 

 wards, and separate. Limbs two in front and weak, with 

 ftye nearly equal toes. Pores before vent distinct. 



Section. SQUAMATA, OR SCALED 

 REPTILES. Body covered with overlapping scales. 

 Skull formed of separate bones ; bone of ear external and 

 jointed to skull. Tongue free, long, and nicked at the tip. 



Order. SAURA, OR LIZARDS. Mouth not di- 

 latable, jaws toothed, bones of lower jaw united in front. 

 Limbs four, and mostly distinct ; toes clawed. Body long 

 and rounded. Eibs distinct, and moveable. Tail long and 

 tapering. Eggs covered with a hard skin. 



Sub-order. LEPTOGLOSS^E. Tongue flat, long, and 

 forked at tip 



Tribe. CYC LOS A URA. Scales of back and tail 

 rounded, or granular ; those of abdomen squared and set in 

 cross bands. Eyes with two valvular lids. Feet strong, 

 toes compressed. 



Family. MONITORIDJE. Head with little, flat, many- 

 sided shields. Tongue sheathed at base. 



Genus. REQENIA. Tail compressed, with keel of double 

 row of scales. Nostrils large, oblique, and new the eyes. 

 Toes short. Africa. 



Genus. MONITOR. Tail as above. Nostrils round, nearly 

 ha'f way between eyes and muzzle. Africa, Asa> and 

 Australia. 



Family. TEIDJE. Head with large, regular, many- 

 sided shields ; teeth solid ; tongue flat and long, mostly 

 free. Scales of back granular or keeled, and rhombic in 

 ehape. Sides flat. Throat scaly, with double collar. All the 

 Teidse inhabit the Western world. 



Genus. TEitrs. Throat with large hexagonal scales be- 

 tween folds of throat. Ventral shields small, long, and 

 smooth. Five toes on each foot. Pores of thigh distinct. 

 Brazils. 



Genus. AMEIVA. Teeth with three lobes, and com- 

 pressed. Ventral shield broad and smooth. Tongue 

 shoathed at base. Brazils and West Indies. 



Genus. CNEMIDOPHORXJS. Tongue not sheathed at base. 

 Toeth compressed longitudinally. Toes five on each fjoot. 



Genus. CENTROPYX. Throat with collar of large shields. 

 Tail round. Scales of back large, those of sides granular. 

 A mcrica. 



Genus. ADA. Collar and ventral shields smooth and 

 long. Tail compressed. Scales of back unequal ; throat 

 with two folds. 



Family. LACERTINIDIE. Head pyramidal, with re- 

 gular many-sided shields. Throat scaly. Tongue long, flat, 

 .and deeply forked. Teeth hollow. Scales of body keeled 

 and rhombic, those of sides small and granular. Sides 

 flattened. 



Genus. ZOOTOCA. Nostrils erect in nasal shield. Toes 

 simpJe and compressed. Collar distinct. Lower eyelid 

 scaly and opaque. Europe, Africa, and Australia. 



Genus. LACERTA. Lower eyelid opaque. Chin fold dis- 

 tinct. Shields of abdomen narrow behind. Europe, Africa, 

 Asia. 



Genus. ACANTHODACTYLTJS. Toes keeled beneath, and 

 fringed on the sides. Palate without teeth. Africa. 



Genus. EREMIAS. Nostril horizontal, between three 

 scales. Eyelid distinct. Toes compressed, keeled beneath, 

 not toothed on edge. Many ventral shields, in several series. 

 Africa. 



Genus. OPHIOPS. Eyelid rudimentary, eye circular and 

 exposed. Palate not toothed. Pores on thighs distinct. 

 Shores of the Mediterranean. 



Family. ZONUBIDJE. Head pyramidal or flattened, 

 with regular many-sided shields. Tongue flat and niched 

 at tip. Scales of back and tail large and rhombic. A fold 

 along the sides. Eyes with two lids. 



Genus. ZONURUS. Head flat. Scales of back and sides 

 square and keeled. Lower eyelid opaque. Tail spined. 

 Pores of thigh distinct and numerous. Africa. 



Genus. PSEUDOCORDYLUS. Head fiat. Scales of back 

 nearly oval, surrounded with granules. Tail spined. Africa. 



Genus. GERRHOSAURUS. Head pyramidal and squared. 

 Tongue scaly. Five toes on each foot. Body spindle- 

 shaped. Tail not spined. Africa. 



Genus. SAUROPHIS. Toes four on each foot, and very 

 short. Body and tail very long. Tail not spined. Africa ; 

 perhaps Australia. 



Genus. TACHYDROMUS. Head pyramidal and long. 

 Collar of keeled scales. Ventral scales keeled. Tail not 

 spined. Asia. 



Gtnus, PSEUDOFUS. Fore pair of limbs wanting, hinder 

 pair very small and undivided. Body snake-like. No pores 

 on thigh. Africa, parts of Europe, and Asia. 



Genus. OPHISAURUS. Limbs wholly wanting. Two 

 deep grooves along body. Palate toothed. North America. 



Family. CHALCID.ZE. Head with regular many-sided 

 shields. Tongue scaly, palate without teeth. Limbs four, 

 but very sina.1 and feeble. No pores on thigh. Body long 

 and cylindrical. 



Genus. CHALCIS. Hinder feet not divided. Scales 

 square. America. 



Family. ANADIADJE. Lower eyelid transparent. Scales 

 of back and sides six-sided, not overlapping ; those of 

 abdomen four-sided, and arranged in longitudinal series. 

 Sides rounded. Limbs four, five toes on each foot ; numerous 

 pores on thigh. 



Oenus. ANADIAS. Same characteristics. America. 



Family. CHEIROCOLID1E. Lower eyelid transparent 

 Tongue scaly. Collar double. Ears under skin. Body and 

 tail long and nearly cylindrical. Scales of back, sides, an-1 

 tail long, sharp, overlapping, and keeled, arranged in alter- 

 nating rings. Legs four, and short ; pores numerous ; toes 

 five on each foot, hinder toes very long. 



Genus. HETERODACTYLUS. Same characteristics. Ame 

 rica. 



Family. CERCOSATTRIDIE. Upper eyelids very short. 

 Ears distinct. Sides rounded with scales like those of back. 

 Large keeled scales in series along back and upper part of 

 tail. Under parts with flat squared scales. Limbs four, 

 toes five on each foot, tail round. 



Genus. CERCOSAURA. Body long; scales of back oblong, 

 with blunt keels. No pores on thighs. America. 



Family. CHAMLESAURID-S;. Palate without teeth. 

 Lower eyelid scaly. Body and tail long, and covered with, 

 regular rings of keeled scales. Limbs rudimentary. Ears 

 distinct and small. Sides without groove, and scaled like 

 back. 



