1. ZONITRITS. 



257 



regular longitudinal, and twenty-three to twenty-seven transverse 

 series, those of the outermost series shortly mucronate and frequently 

 feebly keeled. A ])air of enlarged posterior proeanal scales. Limbs 

 above with large spinosc, serrated, imbricate keeled scales, inferiorly 

 with smooth or feebly keeled ones. Femoral pores six to nine on 

 each side. Tail with whorls of large, strongly keeled, spinose, ser- 

 rated scales, the spines strongest on the sides. Upper parts yellowish, 

 olive, or blackish-brown, uniform or variegated with dai-ker ; some- 

 times a reddish band along each side ; lower surfaces yellowish or 

 greenish white. 



millira. 



Total length 174 



Head 24 



Width of head 19 



Body 60 



millira. 



Fore limb 30 



Hind limb 41 



Tail 90 



H. Trevelyau, Esq. [P.]. 



F. P. M. Weale, Esq. [P.]. 

 Prof. Busk [P.]. 

 Earl of Derbv [P.]. 

 C. Darwin, Esq. [P.]. 



(Types of Z. vertebralis.) 



5. Zonurus polyzonus. 



Cordylus polyzonus, Gray, Cat. p. 47. 

 Cordylus polyzonus, Smith, Mag. N. H. (2) ii. 1838, p. 34, and III. 



S. Afr., Rept. pi. xxviii. fig. 1, and xxx. fig. 7. 

 Zonurus polyzonus, Dum. ^" Bibr. v. p. 357 ; Peters, Mon. Berl. Ac. 



1802, p. 18. 



Head and body much depressed. Head longer than broad, with 

 slightly rugose shields. Nasal very small, pierced posteriorly ; a 

 larger supranasal forming a suture with its fellow ; frontonasal hexa- 

 gonal, broader than long, followed by a pair of prasfrontals ; frontal 

 hexagonal or pentagonal, slightly wider anteriorly ; interparietal 

 small, (luadrangular, in the middle between tlie two pairs of parietals, 

 the posterior of which is a little larger than the anterior ; temporals 

 strongly keeled, in five or six longitudinal rows, upper smallest ; a 

 short spine in front of the ear ; four su])raoculars, anterior largest ; 

 three supraciliaries ; a loreal, a larger pncorbital ; three infra- 

 orbitals, second descending to the lip, separating the fourth and 

 fifth labials ; six upper labials ; rostral three to four times as broad 

 as high. ^lental pentagonal or tetragonal ; six lower labials, 



VOL. II. a 



