274 
Transactions of tJie JRoyal Society of South Africa. 
A. Forma typica. 
Daudin's description is drawn up from two specimens stated to be in 
the Paris Museum.* The diagnosis is : " Occipite spinosissimo, corpore 
supra fusco squallido sub-atro, vittd longitudinali flavescente supra dorsum, 
abdomine guldque ccerulescentihus, caudd suh-compressd .''^ The habitat was 
unknown, but Dumcril and Bibron, who have fixed the definition of this 
species, say it is common at the Cape of Good Hope. I have therefore 
based the following description on specimens from the S.W. parts of South 
Africa, which may safely be regarded as representing A. atra in the sense 
given to it by Daudin and by Dumeril and Bibron. 
Form . — Head and body much depressed. Head as long as broad ; snout 
short, rounded or obtusely pointed ; canthus rostralis very short ; nostril 
directed upwards and backwards, in a very convex, subtubular shield, pierced 
on the canthus rostralis ; length of head 3f to 5 times in length to vent. 
Diameter of ear-opening equal to, or slightly less or slightly more than cleft 
of closed eye. Limbs strong, moderately elongate ; the hind limb, pressed 
against the body, reaches the shoulder, the neck, or the ear ; length of hand 
greater than depth of head ; fingers short, third and fourth equal or fourth 
slightly the longer ; tibia as long as the head or the foot, or a little shorter or 
longer ; toes thick and short, third and fourth equal or fourth (very rarely 
third) slightly the longer, fifth extending as far as first or a little farther. 
Tail cylindrical in females, more or less compressed in males, longer (lyy to 
1^ times) than head and body. 
Measurements : 
1. 
2. 
8. 
4. 
Snout to vent 
82 
116 
93 
101 
Head ..... 
21 
30 
22 
23 
Width of head . 
21 
30 
22 
23 
Depth of head 
11 
16 
12 
14 
Diameter of eye-cleft . 
3-5 
4-5 
4 
4-5 
,, ear-opening 
3 
4 
3-5 
4-5 
Fore limb .... 
43 
52 
44 
51 
Hand ..... 
16 
18 
15 
18 
Hind limb .... 
60 
80 
61 
74 
Tibia 
20 
29 
21 
26 
Foot ..... 
20 
27 
21 
26 
Tail 
111 
145 
103 
124 
1. ^, Simon's Bay. 2. ^, Deelfontein. 3. ?, Deelfontein. 4. 
Klipfontein. 
Lepidosis. — Scales of upper parts very small (105 to 150 round middle 
of body) subequal or intermixed with few, irregularly scattered, enlarged or 
They do not seem to have been preserved, as they are not mentioned in 
A. Dumeril's Catalogue of 1851, p. 101. 
