2. opnisAURUS, 283 



4. OpMsaiirus gracilis. (Plate XV. fig. i.) 



Pseiidopus gracilis, Orrii/, Cat. p. o6. 

 Dopasia c^-acilis, Grm/, Arm. cV M(i(/. ^\ Jl. (2) xii. 1853, p. 389 ; 



Giinth. Proc. Zool. Soc. 18G0, p. 172, 

 Opliiseps tessellatus, Bhjth, Journ. As. Soc. Bencf. xxii. 1853, p. 055. 

 PseudopiLs gracilis, Giinth. liejit. Brit Inch p. 75; Anders. Proc. 



Zool. Soc. 1871, p. 156. 



Lateral teeth conical ; one or two series of teeth on the pterygoids. 

 Azj-gos pra?frontal narrower than the greatest width of the frontal, 

 usually separated from the latter by two or three prajfrontals on a 

 transverse series ; interparietal broader than the parietals, as broad 

 as or broader than the occipital ; three shields on a line from the 

 nasal to the azygos pra^frontal ; live supraoculars. Ear-opening 

 distinct, not larger than the nostril. Dorsal plates in fourteen longi- 

 tudinal and one hundred to one hundred and ten transverse scries, 

 keeled ; ventrals in ten longitudinal series, smooth. No rudiments 

 of limbs externally. Tail about twice as long as head and body ; 

 upper caudal scales keeled, lower less distinctly. Brown above, with 

 a darker lateral band, and frequently with irregular transverse series 

 of bluish, black-edged spots ; lower surfaces pale brownish or yel- 

 lowish. 



From snout to vent 12 ccutim. ; tail 2.5. The largest specimen, 

 with reproduced tail, measures 19 centim. from snout to vent. 



Eastern Himalayas, Khasia hills. Eastern Bengal, Burma. 



5. Opliisaurus koellikeri. (Plate XY, fig. 2.) 



Hvalosaurus koellikeri, Giinth. Ann. <§• 3Iac/. N. H. (4) xii. 1873, 

 p. 351. 



Lateral teeth conical ; two series of teeth on the pterygoids, one 

 on the palatines. Azygos prsefrontal large, quite as broad as the 

 frontal, with the entire anterior border of which it forms a suture ; 

 interparietal much broader than the parietals or the occipital ; two 

 shields on a line from the nasal to the azygos prajfrontal ; five 

 supraoculars. Ear concealed. Dorsal plates in fourteen longitu- 

 dinal and one hundred and twenty transverse series, the median 

 obtusely keeled, the laterals smooth ; ventrals in ten longitudinal 

 scries, smooth. Rudiments of hind limbs, as in 0. apus. Ujjpcr 

 and lower caudal scales keeled. Brownish above, with a darker 

 lateral band and small dark-brown spots on the middle line of the 

 anterior part of the back ; belly yellowish. 



Erom snout to vent 13 centim. 



Bab. ? 



a. Ilgr.? ? (Type.) 



