dark blotches described in treating of the colouring of this lizard; other
folds, though not so distinctly marked, are observed to traverse the upper
surface of the neck, and, like those of the sides, evidently result from the
skin on these situations being more extensive than the parts it is destined to
cover, in order to permit the head to move freely. The skin of the back of
the neck, and of the back and sides of the body, is covered with two descriptions
of scales, the one description considerably larger than the other, more
or less orbicular, and disposed in rows, which can be traced either longitudinally
or transversely, and each of these scales is more or less carinated, particularly
towards its posterior edge, the carince; however, are less acute in
adult specimens than in young ones, and less on the sides than the back,
probably from the effects of friction. The second description of scales occur
in the interstices between the ones just described, and are very small, somewhat
circular, and without keels, and the sides of the neck are entirely
coated with scales of this description. The superior and hitfder surfaces of
the leg are covered with somewhat diamond-shaped scales, all of which
are strongly keeled, and the keel of each posteriorly forms a sharp elevated
spine; the scales coating the under and anterior surfaces of the fore-legs
smaller than those on their upper part, and with less distinct keels. Those
of the anterior and inferior surfaces of the hinder leg, large, flat, somewhat
quadrangular, and without keels. Feet rather slender, and covered with
keeled scales. Toes long, delicate, and free. Claws short, curved, pointed,
and laterally compressed. Chin and anterior part of throat covered with
small, somewhat quadrangular scales; posterior part of throat and space
between fore-leg coated with large, imbricate, irregular scales, not in distinct
rows; rest of under part of body with ten rows of four-sided plates, the
greatest length of each plate transversely. Tail rigid, and very hard, thick
at the base, from whence it tapers to a fine point; above it is flat and rather
broad, below narrow and slightly rounded, hence its section exhibits somewhat
of a triangular form, two angles being formed by the edges of the upper
surface, and the third by the under surface. The scales on this part of
the reptile are disposed in rings, towards the base each ring consists
of two circles of scales, and towards the apex only of one; all the scales of
the upper and lateral parts are carinated, and the carince are most
developed in those situated over the lateral angles, particularly towards the
base of the tail, where they terminate posteriorly in prominent sharp spines.
On the lower parts of the sides, and on the centre of the upper surface, the
keels are much less marked, and are not prolonged into acute spines;
towards the point of the tail the keels are acute, but do not end in spines.
Where the rings consist of two circles of scales, the scales of the circle
nearest to the body are always smallest, and the keels but scarcely visible.
The under-surface of the tail, towards its base, coated with two rows of flat
square scales, towards the point with keeled ones, like those of the sides and
upper surface. Meatus externus large, vertically ovate, and opening outwards
and backwards, under the projecting edge of the temple. Nostrils
small, circular, and placed near to the apex of the muzzle. Eyes moderately
large, rather deeply set, and the eyelids, particularly the lower ones, covered
with small granular scales. Femoral pores in one, two, or three rows, each
of a circular shape, and its interior consisting of a sort of fungoid texture,
which generally protrudes beyond the investing membrane. Full-grown
specimens of this species vary from twelve to eighteen inches in length, and
the tail generally measures more than the other parts.
Each of the varieties figured appears to be restricted to its own localities; and, as far as my
observations extend, no specimens of two varieties are ever found in the same districts. All
the varieties inhabit rocky situations, and where they have a choice they invariably prefer precipices,
and the stoney walls of difficultly accessible ravines. In these situations they wander
carelessly in search of food and warmth, unless alarmed by what they may regard as enemies.
On being closely approached in their retreats they seek concealment under rocks, or in crevices;
and when they get into such positions they are with difficulty" captured, as by aid of the
prominences on the hinder edge of each temple they hold on with a tenacity which is quite
surprising, and by them they occasionally offer such an effectual resistance to the force
applied from behind, that the tail breaks off from the body before the reptile is secured.
The variety represented in Plate XXIV., Fig 1 ;.is found on Table Mountain, and the hills near
Cape Town; that on the same plate, and lettered 2, is an inhabitant of rocky precipices at
and around Algoa Bay. The variety represented in Plate XXV. occurs on the hills between
the principal branches of the Orange River, to the eastward of Phillopolis ; and that figured in
Plate XXVI. is found on the top of the high mountainous range, which extends behind Kaffer-
land and the country of Natal.