SNAKES OF WEST AFRICA. 295 



4. ISTaia goldii Bouleng. Ann. & Mag. N. H. (6) xvi. 1895, 

 p. 34, and Cat. t. c. p. 387, pi. xx. fig. 2. 



Naia guentheri Bouleng. Cat. t. c. p. 388, pi. xxi. 



Sierra Leone to Congo, eastwards to the Ituri and the Kasai. 



4. Dendraspis. 



Schleg. Yersl. Zool. Gen, Amsterd. 1848 ; Bouleng. Cat. Sn. 

 iii. p. 434. 



Two species : — 



Scales ill 15 to 19 rows, outer not shorter than dorsals D. Jamesonii. 



Scales in 13 rows, outer half as long as dorsals D. anffustieeps. 



1 . Dexdraspis jamesonii. 



Maps jamesonii Traill, in Schleg. Phys. Serp., Engl. Transl. 

 p. 179, pi. ii. figs. 19, 20. 



De7idraspis jamesonii Bouleng. t. c. p. 436. 



Tropical Africa, from ISTigeria and Uganda to the Congo and 

 Angola. 



2. Dendraspis viRims. 



Leptophis viridis Hallow. Proc. Ac. Philad. 1844, p. 172. 



Dendrasjns viridis Bouleng. t. c. p. 435. 



Senegal to Niger and S. Thome Id., Gulf of Guinea. 



Family Yiperid^e. 



T. Eye moderate or large, usuallj' separated from the npper labials bj- suboculars. 



A. Upper surface of head with large symmetrical shields ; pupil 



round Causiis. 



B. Upper surface of head with scales ; pupil vertical. 

 1. Subcaudals in two rows. 



Lateral scales not smaller than dorsals, without serr.ated keels Bitis. 



Lateral scales smaller than dorsals, disposed obliquely, with serrated 



keels Cerastes. 



'I. Subcaudals single; lateral scales smaller than dorsals and more or less 

 oblique or irregular. 



Lateral scales with serrated keels Ecliis. 



Lateral scales without serrated keels ; tail prehensile Atheris. 



II. Eye minute, with round pupil ; upper surface of head with 

 large symmetrical shields ; no loreal ; a small prasocular usually 

 present Jtractaspis. 



1. Causus. 

 Wagl. Syst. Amph. p. 172 ; Bouleng. Cat. Sn. iii. p. 465. 



Two species: — 



Scales in 15 to 21 rows; subcaudals in two rows C. rhomheatus. 



Scales in 13 rows ; subcaudal s single C. lichtensteinii. 



1. Causus rhombeatus. 



Sepedou rhomheatus Licht. Verz. Doubl. Mus. Berl. p. 106. 



Caitsits rJiomheatibs Bouleng. t. c. p 467. 



Tropical and South Africa. 



