THE HORNED ADDER, OR HORNSMAN. 241 
Duerden’s Adder, lay eggs, but the Night Adder (Causus rhom- 
beatus) does also. Doubtless the other species of the Genus 
Causus are also oviparous. 
THE HORNED ADDER, OR HORNSMAN. 
The Hornsman is a small adder with the characteristic 
flattish body and broad head of the Viperine family of snakes. 
These vipers are usually about a foot to one foot six inches in 
length. There are two species, the only notable difference 
between them being that the one known as Bitis cornuta has two 
or more erect horn-like scales over each eye, while the other, 
which is known as Bitis caudalis, never has more than one erect 
horn-like scale over the eye. The former occurs in the sandy 
districts of the Western Province of the Cape Colony and north- 
wards to German West Africa. The latter is found in the midlands 
of both provinces of Cape Colony, and extends to Rhodesia. They 
have a habit of burying their bodies in the loose sand, the head 
only being above. In this position they will lie for hours, often 
for a whole day on the watch for lizards and other small creatures 
on which ‘they feed. Being practically invisible when thus 
concealed, they are especially dangerous to the bare-footed native, 
who is bitten the instant he places his foot upon one, unless he 
luckily happens to step right upon its head. Even then the 
chances are the snake will extricate its head in time to deliver a 
bite before the foot has been withdrawn. These snakes are 
capable of inflicting a bite which will cause death to a man. 
However, the chance of a fatal issue is considerably less than if 
bitten by a Puff Adder or Cobra. This adder gets its name of 
Hornsman from the fact of its having two or more erect scales 
on its eyebrows, which look like tiny horns. They give birth to 
young, usually a dozen to sixteen in number, in the early autumn. 
Unless kept in captivity in a large cage out in the open in 
which plenty of sand is strewn, these snakes will not live, as they 
refuse to eat,and die in a short time. They are, moreover, very 
susceptible to a change of environment. I have obtained scores 
of them (Bitis caudalis) from the Karroo and endeavoured to 
keep them alive at Port Elizabeth without success. The atmo- 
sphere is evidently too moist for them. The dry sandy wastes 
are their natural habitats. 
R 
