504 ‘VIPERID2&, 
unequal or subequal scales above, 9 to 13 across from eye to eye; 
no “horns”; 9 to 14 scales round the eye; 3 or 4 series of scales 
between the eye and the labials; nostril between two small shields, 
separated from their fellows by 5 or 6 series of scales and from the 
rostral by one or two; 10 to 12 upper labials ; three lower labials 
in contact with the chin-shields. Scales in 23-27 rows. Ventrals 
102-122, rather strongly keeled laterally ; anal entire ; subcaudals 
18-26, small, and often more or less distinctly keeled. Yellowish, 
pale brown, or reddish above, with or without darker spots; end 
of tail often black; lower parts white, 
Total length 340 millim. ; tail 30. 
Northern border of the Sahara, from Algeria to Egypt. 
a-b. g (Sc. 23; V. 107; Duirat, 8. Tunisia. Dr. J. Anderson [P.]. 
©. 28) & Q (Se. 28; 
V. 117; ©. 22). 
¢, d, e.g (Se. 25, 25; V. Tripoli. T. Ritchie, Esq. [P.]. 
105, 102; ©. 22, 22) (Type of C. ritchie.) 
& $, (Se. 25; V.109; 
f é {se 25; V. 119; Gizeh, Egypt. Dr. J. Anderson [P.]. 
) 
g: é (Se. 25; V. 111; Abu Roash, Egypt. Dr. J. Anderson [P,]. 
h. oe (Sc. 27; V. 117; BeniHassan,Egypt. Dr. J. Anderson [P.]. 
26 
. 26). 
a-l. g (Sc. 24; V.107; Desert coast W. of Dr. J. Anderson [P.]. 
C. 25) & 2 (Sc. 28, Suez Canal. 
25; V. 110, 112; C. 
21, 22). 
7. ECHIS. 
Pseudoboa, part., Schneid. Hist. Amph, ii. p. 281 (1801). 
Scytale, part., Daud. Hist. ni ef (1803). 
Echis, part., Merr. Tent. Syst. Amph. p. 149 (1820) ; Jan, Elenco 
sist, . p. 122 (1863). 
xchis, Wagl. Syst. Amph. as 177 (1830); Gray, Zool. Miscell. p. 70 
(1842), and Cat. Sn. p. (1849); Dum. §& Bibr. Erp. Gén. vii. 
p- Sart (1854) ; 118 Gb = fsivs Sy ve (1864) ; Strauch, 
m. Viper. p. ); Bouleng. Faun. Ind. t. p. 421 
(1890), and Trans. Zool. Soc’ xiii. 1801, p.155. nee 
Vipera, part., Schleg. Phys. Serp. ii. p. 578 (1887). 
Toxicoa, Gray, Cat. p. 29. 
Head very distinct from neck, covered with small imbricate 
scales; eye moderate, with vertical pupil, separated from the 
labials by small scales; nostril directed upwards and outwards, in 
a single or divided nasal, Body cylindrical; scales keeled, with 
apical pits, in 27-37 rows ; dorsal scales forming straight longitu- 
dinal series ; lateral scales smaller, oblique, pointing downwards, 
ibe serrated keels; ventrals rounded. Tail short; subcaudals 
single. . 
Africa north of the Equator, Southern Asia, 
