SNAKES. 29 
4. Ecuis. 
Subcaudal plates one-rowed: nostrils minute, in suture of two 
small scales: the anterior frontal shields minute, smooth: pupil 
round: eyes surrounded by small scales: superciliary shield small, 
scale-like or single, elongate and distinct: scales elongate, keeled 
to the tip. 
Echis, Merrem, Tent. 149, 1820. Gray, Zool. Mise. 96. Wag- 
ler, Syst. 177. Scytale, Latr. Rept. iii. 158. Daud. v. 339. Cuvier, 
R. A. ii. 79, not Merrem. Boa sp., Shaw, Zool. 
* Superciliary shields small, like a scale. Toxicoa. 
1. The Toxicoa. Echis arenicola, Bote, sts, 1827, 558. Gale- 
rie, Zool. t.48. Wagler, Amph.177. Gray, Zool. Mise. 96. Vipera 
pyramidarum, Geoff: Rept. Egypt, t.7, f.1. Savigny, R. E. t. 4, 
f.1—4. Vipera Hgyptiaca, Ruppell, Mus. Francf. Echis pavo 
and Echis varia, Reuss. Mus. Senk. ii. 137, 160, t.7, f.2.  ? Col. 
Libetinus, Linn. Mus. Ad. Fr. ii. 43. S. N.i. 165. Forskal, Faun. 
Arab. 13. Vipera Libetina, Latr. Rept. iii. 324? Daud. Rept. v. 
137? Vipera Echis, var. 2, Schlegel, Phys. Serp. 583. 
Superciliary scales small, like the other ocular ones: gray- 
brown, with angular white streaks, and a series of whitish vertebral 
spots: crown dark, varied with arrow-shaped white streaks. 
a—c. In spirits. Adult. Nw Africa, Egypt. Presented by Sir J. 
Gardiner Wilkinson. 
** Superciliary shields elongate, distinct. Echis, Merrem. 
2. The Horarra Pam. Echis carinata, Merrem Tent. 149. 
Wagler, Amph. 177. Gray, Zool. Misc. 96. Horatta Pam, Russell, 
Ind. Serp. ii. t.2. Boa Horatta, Shaw, Zool. iii: 359. Pseu- 
doboa carinata, Schneid. Hist. Amph. ii. 285. _Scytale bizonata, 
Daud. Rept. v. 339, t. 70. Vipera Echis, var., Schlegel, Ph. Rept. 
583, t. 21, f. 10, 11. ? Boa Krait, Williams, Asiat. Research. 
ii. 328. Pseudoboa Krait, Schneid. Amph. ii. 288. Scytale Krait, 
Daud. Rept. v. 326. Echis Krait, Merrem, Tent.149. _ E. ziczae, 
Gray, Ann. Phil. 1825, 205. 
Superciliary scales elongate, larger than the others: gray- 
brown, with angular white streaks: crown of head dark, with large 
dark-edged oblong spots. 
D3 
