332 THE EEPTILES OF EGYPT. 
having a more or less brownish tint ; head immaculate or spotted with dark brown ; 
generally a dark brown oblique band from behind the eye, very distinct in some, obscure 
in others, and occasionally an oblique spot below the eye ; under surface yellowish ; tip 
of tail occasionally blackish. 
It ( 6 ) attains to 735 millim. in length, of which the tail forms 55 millitn. 
This species is common on the margin of the desert along the Nile, and has been 
recorded from the Bayuda desert and as far south as Sennaar (Bruce). It occurs 
also along the shores of the Red Sea from Suez to Suakin, and is therefore probably 
distributed all over the region between the Nile and the Red Sea. On the west of that 
river it is in all likelihood spread over the entire Saharian desert and its oasis. Bruce 
found it to be extremely common in Cyrenaica, and it also occurs in Tunisia and Algeria. 
It is present in Arabia (Sinai tic Peninsula and Hadramut) and in Southern Syria. 
Its food consists of small rodents, such as members of the genera Mas, Gerbillus, 
and Jerboa. Bruce, on the only occasion in which he met with an animal in the 
stomach of this species, found a Jerboa l . 
Its habit is to conceal itself in the sand of the desert, only its eyes and the upper 
part of its head being visible. This was known to Pliny 2 , who, however, says that it 
often had two pairs of horns 3 , and that these organs were to entice birds 4 to it ; and 
Belon fancied that he saw in them a resemblance to grains of barley ! Daudin suggests 
that it was probably owing to this supposed likeness that Pliny and Solinus described 
the Cerastes as hiding under leaves. 
The majority of the specimens collected by me were dug out of holes that might 
have been tenanted by rodents. Bruce styles this viper the companion of the Jerboa, 
and there can be no doubt that it is generally found in localities in which that rodent 
abounds, associated with others, such as Mus and Gerbillus, all of which are either 
crepuscular or nocturnal in their habits, like the viper itself. Wilkinson 5 mentions 
that he met with an example of this species on the island in the middle of Lake 
Mceris, a rather remarkable place in which to find a viper, as these snakes do not, as a 
rule, enter water, at least they are generally credited with not doing so. According to 
Bruce this snake is able to endure the absence of food for a very long period, as 
1 Travels, v. 1790, Appendix, p. 202. 
2 Hist. An. viii. 23. 
3 "Wilkinson (Anc. Egypt, iii. 1S78, p. 339) mentions that snake-catchers in his day offered horned 
vipers for sale with four horns, the extra pair being clearly introduced beneath the scales. Others he 
mentions had occasionally long flowing hair on their heads. 
' Viperine snakes have not generally been credited with the above habit of capturing birds, but that 
the true vipers occasionally do so is proved beyond doubt by the fact recorded by Gunther that he removed 
a Saxicola from the stomach of V. lebetina (Proc. Zool. Soc. 1879, p. 741). 
5 Ancient Egyptians, iii. 1878, p. 339. 
