1. zonurvs. 253 
Synopsis of the Species. 
I. Frontonasal in contact with the rostral; scales of the flanks 
separated from one another by granular intervals. 
Head with large spines posteriorly.... 1. giganteus, p. 253. 
Head without spines .............. 2. tropidosternum, p. 254. 
II. Frontonasal separated from the rostral. 
A. Flanks with scales like the dorsals. 
a. No supranasals ; lower eyelid opaque. 
Nasal swollen, hemispherical, pierced 
in the centre; temporal spines .... 3. cataphractus, p. 255. 
Nasal not swollen, pierced posteriorly ; 
no temporal spines .............. 4. cordylus, p. 256. 
b, A supranasal, nasal very small; lower eyelid with a 
transparent disk. 
Anterior gular scales flat, moderate .. 5. polyzonus, p. 257. 
Anterior gular scales almost granular. 6. pustulatus, p. 258. 
B. Flanks granular............ 7. capensis, p. 258. 
1. Zonurus giganteus. 
Zonurus derbianus, Gray, Cat. pp. 48, 270. 
Cordylus giganteus, Smith, Ill. 8. Afr., Rept. pls. xxxv., Xxxvi. 
Head longer than broad. Head-shields very rough; frontonasal 
slightly broader than long, in contact with the rostral, separating 
the nasals ; latter not swollen, the nostril pierced in the postero- 
inferior corner; prefrontals forming a suture; frontal hexagonal, 
slightly widened anteriorly ; frontoparietals longer than broad ; 
-interparietal as large as, and on a line with the anterior parietals, 
forming a suture with the postfrontals ; posterior parietals much 
larger than anterior ; four large, striated occipital spines, the inner 
shorter and slightly curved inwards, the outer largest, directed 
obliquely outwards, as long as the three anterior supraorbitals ; 
temporal shields large, keeled; four subtriangular, slightly curved 
temporal spines on each side, the upper nearly as large as the 
median occipitals; supraoculars four, anterior largest, second 
broadest ; three supraciliaries ; lower eyelid opaque ; a small loreal 
or postnasal and a large preorbital ; two infraorbitals ; six or seven 
upper labials, fourth or fifth smallest; rostral six-sided, twice and 
a half as broad as high. Mental large, pentagonal; five lower 
labials, fifth largest and keeled ; a row of five large shields borders 
the lower labials, and there is a median chin-shield behind the 
anterior pair; gular scales moderately large, subtriangular, strongly 
imbricate, feebly keeled; scales on the collar large, lanceolate, 
