1. GERRHONOTUS.—2. OPITISAURUS. 279 
between the prefrontal and the rostral; nasal separated from the 
rostral ; a supranasal ; two superposed postnasals ; one loreal and a 
large canthal descending between the latter shield and the pre- 
ocular; three outer supraoculars ; ten or eleven upper labials. A 
rather narrow granular zone along the side of the neck. Lateral 
fold strong, extending on the neck. Dorsal scales in eighteen or 
twenty longitudinal series, the six median strongly keeled, the 
others smooth or indistinctly keeled; fifty-two to fifty-four trans- 
verse series; ventrals larger than dorsais, in twelve longitudinal 
series. The adpressed fore limb reaches the eye ; the length of the 
hind limb equals half or three fifths the distance from axil to groin. 
Tail subquadrangular at the base; upper caudal scales strongly 
keeled. Olive-brown above, back uniform or black-spotted, sides 
spotted with black and greenish white; lower surfaces greenish 
white, uniform or with scattered blackish dots. 
millim. millim. 
Total length (tail re- BOY 326 0 yeaa 3 76 
produced) ...... 185 Fore limb ........ 22 
Heads. ae ew cates 18 Hind limb........ 28 
Width of head .... 12 
Guatemala; Vera Cruz. 
a-b. Q. Lanquin, Vera Paz, O. Salvin, Esq, (C.]. 
a S. Duenas. O. Salvin, Esq. [C.]. 
d. Q. Rio Chisoy. O. Salvin, Esq. [C. ]. 
2. OPHISAURUS. 
Ophisaurus, Daud. Rept. vii. p. 846; Fitzing. N. Classif. Rept. p. 20 ; 
Wagler, Syst. Amph. p. 159; Wiegm. Herp. Mex. p. 11; Dum. § 
Bibr. v. p. 421; Gray, Cat. Liz. p. 56. 
Bipes, Oppel, Ordn. p. 43; Wagl. lc. 
Pseudopus, Merrem, Tent. p. 78; Fitzing. l.c.; Wiegm. l.c.; Dum. 
& Bibr. lc. p. 412; Gray, l.c.; Giinth, Rept. Brit. Ind. p. 74. 
Hyalinus, Derr. 1. c. p. 79. 
Proctopus, Fischer, Mém. Soc, Nat. Mosc. iv. 1830, p. 241. 
Dopasia, Gray, Ann. § Mag. N. H. (2) xii, 1853, p. 389. 
Ophiseps, Blyth, Journ. As. Soc. Beng. xxii. 1853, p. 655. 
Hyalosaurus, Giinth. Ann. § Mag. N. H. (4) xii. 1878, p. 351. 
A lateral fold. Scales squarish-rhomboidal, forming straight 
longitudinal and transverse series. Limbs absent externally, or 
reduced to a rudiment of the hind pair. Teeth with conical or sub- 
spherical crowns. Pterygoid teeth ; palatine and vomerine teeth 
present or absent. 
South-eastern Europe, North Africa, South-western Asia, Hima- 
layas and Burma, South-eastern North America and Mexico. 
