AFRICAN SNAKES. 199 



Family Boid^e. 

 Two genera : — 



Head distinct from neck ; rostral and anterior upper labials with deep 

 pits ; scales in more than 50 rows ; tail prehensile, tapering to a 

 point, with paired subcaudals Python. 



Head not distinct from neck ; rostral large, not pitted ; scales in 29-32 

 rows; tail short, rounded at the end, with single subcaudals Calalaria. 



1. Python. 

 Daud. Hist. Rept. v. p. 266 ; Bouleng. Cat. Sn. i. p. 85. 

 Two species : — 



Two upper labials pitted ; scales in 81-93 rows ; subcaudals 63-77. P. sebce. 

 Five upper labials pitted ; scales in 57-59 rows ; subcaudals 46-47. P. anchieta. 



1. Python sebjs. 



Coluber sebce Gmel. S. N. i. p. 1118. 

 Python sebce Bouleng. t. c. p. 86. 

 Python natalensis Bocage, Herp. Aug. p. 72. 

 Tropical and South Africa. 



2. Python anchiet^e Bocage, Jorn. Sc. Lisb. xii. 1887, p. 87, 

 and Herp. Ang. p. 73, pi. ix. fig. 1 ; Bouleng. t. c. p. 88. 



Angola (Catumbella). 



2. Calabaria. 



Gray, P. Z. S. 1858, p. 154 ; Bouleng. Cat. Sn. i. p. 92. 



1. Calabaria reinhardti. 



Eryx reinhardti Schleg. Bijdr. tot de Dierk. i. p. 2, pi. — . 



Calabaria reinhardti Bouleng. 1. c. 



West Africa, from Liberia to the Congo. 



Family Col u bridge. 



Three parallel series : — 



No poison-fangs ; all the teeth solid A. Aglypha. 



Poison-fangs behind B. Opisthoglypha. 



Poison-fangs in front C. Proteroglypha. 



A. Aglypha. 



I. Loreal present (occasionally absent in Homalosoma, recognisable by the 

 combination of a single nasal shield, paired subcaudals, and a low number of 

 ventral shields, 113-144). 

 A. Snout without angular horizontal edge. 



1. Pupil round ; a single anterior temporal ; scales in 17 to 23 rows ; ventrals 

 less than 165. 

 a. No groove on side of head. 



a. Two internasals Tropidonotus. 



(3. A single internasal. 



Scales smooth, in 19 rows Helicops. 



Scales keeled, in -23 or 25 rows Hydrcethiops. 



