COMPENDIUM OF GENERIC DISTINCTIONS. 



777 



Genus. CERBERUS. Head shielded, scaled above ; nos- 

 trils in centre of shield. Scales of body keeled and grooved, 

 asm. 



Family. BOID.&. Hinder limbs developed under skin, 

 and protruding in form of a horny spur on each side of the 

 base of the tail. Tail short. 



Section I. Tail strong and prehensile. Muzzle blunt, 

 nead distinct. 



Genus. MORELIA. Crown of head with scale-like plates. 

 Deep pits on lip-shields. Pupil of eye elliptical and erect. 

 Plates under tail two-rowed. Australia. 



Genus. PYTHON Crown of head shielded to behind 

 eyes, rest scaled. Pits on lip-shields. Pupils of eyes linear 

 and erect. Plates under tail two-rowed. India. 



Genus. HORTULIA. Head with irregular scales, shielded 

 in front of forehead and on muzzle. Pits on lip and rost. al 

 shields. Plates under tail two-rowed. Africa. 



Genus. EPICRATES. Scales smooth, plates under tail 

 one-rowed. Crown of head scaly. America. 



Genus. XIPHOSOMA. Lip-plates short and all pitted. 

 Rest as in Epicrates. America. 



Genus. BOA. Scale? smooth. Lip-shields short, not 

 pitted. Crown of head scaled ; nostrils at sides, between 

 two plates. America. 



Genus. EUNECTES. Crown with irregular shields; nos- 

 trils between three plates. America. 



Genus. CHILABOTHRUS. Crown of head with regular 

 shields ; nostrils between three scales. Jamaica. 



Section II. Tail very short, rarely prehensile. Head short 

 and indistinct. 



Genus. TORTRIX. Seven shields on head. Pupil of eye 

 circular and covered with a plate, transparent in centre. 

 Scales smooth. One row of plates under tail. Spurs very 

 small and sunk in pits. Tropical America. 



Sub-order. COLUBRIN^E. Abdomen with broad, band- 

 like plates. Spurs none. Both jaws toothed. Tail conical 

 and tapering. 



Section I. No grooved or perforated fang in front of the 

 jaw. 



Family. C ALAMARID.&. Body cylindrical. Head not 

 distinct from neck, gape small, nostrils small. No keels on 

 plates of abdomen. 



Genus. CONOCEPHALUS. Scales above keeled, in seven- 

 teen rows. Two rows of plateo under tail. Head conical 

 and narrow. Teeth equal and smooth. America. 



Family. CORONELLID^. Belly flat, back broad. Head 

 rather flat, shields of head regular. Front teeth shortest. 



Genus. PSAMMOFHYLAX. Rostral shield not protruding, 

 rounded, and with a long process pointing backwards. South 

 Africa. . 



Genus. CORONELLA.- Rostral shield moderate; muzzle 

 short, rounded ; and flat above. Last maxillary tooth smooth 

 or grooved, and rather larger than the others. Most parts 

 of world. 



Family. NATKICID-ffi. Body rather stout. Tail dis- 

 tinct. Head broad and distinct from neck, muzzle rounded. 

 Gape wide. No keels on plates of belly. 



. Genus. TROPIDONOTUS. Scales of back keeled. Muzzle 

 rather narrow. Last maxillary tooth longest. Frontal scales 

 narrow. Most parts of world. 



Genus. HETERODON. Body short and thick, head short 

 and flat ; rostral shield with a sharp ridge above. America 

 and Madagascar. 



Family. COLUBRIN.. Body moderate, tail tapering. 

 Shields of head irregular. Scales oval, overlapping, and 

 nearly equal Two rows of scales under tail. Teeth not 

 grooved. 



Genus. COLUBER. Rostral shield moderate and rounded. 

 Body with rounded back. Teeth equal. Europe, Asia, and 

 North America. 



Genus. CORYPHODON. Teeth of jaws increasing in size 

 behind and smooth. Asia, Africa, and America. 



Family. DKYADID^E. Body very long ; tail long and 

 gradually tapering. Head distinct fiom neck. Shields of 

 head regular. Scales long and lancet-shaped; two rows 

 beneath the tail. 



Genus. HERPETODRYAS. Body slightly compressed. Two 

 nasal shields. Teeth equal and smooth. America. 



Genus. CYCLOPHIS. Body rounded ; one nasal shield. 

 Teeth equal and smooth. East Indies and North America. 



Genus. PHILODRYAS. Hinder jaw-teeth grooved. South 

 America and Madagascar. 



Genus. DROMICUS. Hinder jaw-tooth separated from 

 others by a space, longest and not grooved. West Indies 

 and South America. 



Family. KACHIODONTID-ffi. Tail tapering, head short 

 and high, snout short and blunt. One nasal shield, one 

 anterior and two posterior oculars ; those on crown small and 

 regular. Scales keeled, lancet-shaped. Throat-teeth formed 

 by processes of neck vertebrae. Africa. 



Genus. DASYPELTIS. As family. 



Family. DENDROPHIIXffi. Body very long and slender, 

 rather five- sided. Upper jaw longer than lower. Shields of 

 head long and regular. Scales very narrow. 



Genus. BUCEPHALUS. No keels on plates of abdomen. 

 Head stout, eyes very large. Africa. 



Genus. AH^ETULLA. Slight keels on plates of abdomen. 

 Head long, crown flat. Africa and South America. 



Family. DRYIOPHID^E. Body very long and slender ; 

 head long, narrow ; snout lengthened. Upper jaw much 

 longer than lower ; rostral shield protruding. Scales narrow. 



Genus. DRYIOPHIS. Snout pointed, rostral solid. Africa, 

 Asia, and South America. 



Genus. PASSERITA. Snout with short flexible appendage. 

 India. 



Genus. LANGAHA. Snout with long and scaly appendage. 

 Madagascar. 



Family. DIPSADID.3L Body sjender and compressed. 

 Head short and mostly triangular, sometimes squared. 

 Shields of crown blunt. 



Genus. EUDIPSAS. Head flat and triangular. Scales 

 large over vertebrae. Front teeth of jaws and palate longest. 

 South America and East Indian Islands. 



Family. ELAPID.SC. Head mostly squared, snout short, 

 crown flat. No loreal shield. Scales smooth. Grooved 

 fangs immoveable. 



Genus. BUNGARUS. Scales over vertebrae hexagonal. 

 East Indies. 



Genus. HAMADRYAS. One or two smooth teeth behind 

 fang. Three pairs of large shields round occipitals. East 

 Indian Islands. 



Genus. NAJA. One or two smootn teeth behind fangs. 

 Neck distensible into a hood. East Indies and Africa. 



Genus. ELAPS. No smooth teeth behind fang. Anal 

 scale not cleft. East ladies, Africa, and America. 



Family. DENDRASPID.S!. Long and slender, abdomen 

 flat. Head squared and long, distinct from neck. Perfo- 

 rated fang in front. Front tooth of lower jaw longest. 



Genus. DENDRASPIS. As family. Africa. 



Family. ATKACTASPIDID.fl3. Body rounded, tail ending 

 with sharp conical spine. Head short and flat, not distinct 

 from neck. Perforated fangs in front of enormous length. 



Genus. ATBACTASPIS. As family. Africa. 



Order. BATRACHIA Vertebrate animals, with naked 

 j skin (very rarely with a few imbedded scales). Neck noi 



