COLUBER. 331 



b. Anal usually divided; scales in 23 or 25 



rows. 



a'. Rostral as deep as broad ; normally 8 

 upper labials, 4th and 5th entering eye ; 



subcaudals 79-90 C. liodgsonii, p. 332. 



b' '. Rostral broader than deep ; normally 9 

 upper labials, 5th and 6th entering eye ; 

 subcaudals 90-107 C. tanitmu, p. 333. 



B. Scales strongly keeled on hinder part of back, 



in 19 or 21 rows ; ventrals with an obtuse 



lateral keel. 



a '. Outer caudal .scales without trace of keel. C. radiatm, p. 333. 

 b'. All the caudal scales keeled f. melawmis, p. 334. 



C. Scales smooth or feebly keeled; ventrals with 



well-marked lateral keel ; colour uniform 



green. 



of-. Scales in 19 rows; loreal present C. prasinus, p. 334. 



b'. Scales in 19 rows ; no loreal . . . C.frenatus, p. 335. 



c'. Scales in 25 or 27 rows C. o.rycepJialns, p. 335. 



406. Coluber helena. 



Russell, Ind. Serp. i, pi. xxxii. 



Coluber helena, Daud. Rept. vi, p. 277. 



Cynophis bistrigatus, Gray, A. M. N. H. (2) iv, 1849, p. 246. 



Plagiodon helena, Dum. $ Bibr. Erp. Gen. vii, p. 170 ; Jan, Icon. 



Ophid. 20, pi. iv, fig. 1. 



Herpetodryas malabaricus, Jerdon, J. A. S. B. xxii, 1854, p. 530. 

 Cynophis helena, Giinth. Rept. B. I. p. 247 ; Theob. Cat. p. 167 ; 



Blanf. J. A. S. B. xlviii, 1879, p. 125 ; Murray, ZooL Sind, 



p. 376. 

 Cynophis malabaricus, Giinth. Rept. B. 1. p. 248, pi. xxi, fig. A ; 



Theob. 1. c. p. 167. 

 ? Coluber nuthalli, Theob. Cat. Sept. As. Soc. Mus. 1868, p. 51 ; id. 



Cat. p. 164. 

 Cynophis malabarensis, var. carinata, F. Mitller, Verh. nat. Ges. 



Basel, vi. 1878, p. 671. 



Rostral a little broader than deep, visible from above; suture 

 between the internasals much shorter than that between the 

 prsefrontals ; frontal as long as its distance from the end of the 

 snout, shorter than the parietals; loreal somewhat longer than 

 deep; one large praeocular; two postoculars ; temporals 2 + 2 or 

 2 + 3; 9 (exceptionally 10 or 11) upper labials, fifth and sixth, or 

 fourth, fifth, and sixth entering the eye ; 5 or 6 lower labials in 

 contact with the anterior chin- shields, which are as long as or a 

 little longer than the posterior. Scales in 23 to 27 rows, smooth, 

 or feebly keeled on the posterior part of the body and on the tail. 

 Ventrals 220-265 ; anal entire ; subcaudals 7o-94. Young pale 

 brown above, with black cross bands, each enclosing four to six 

 white ocelli ; adult darker brown, with transverse series of squarish 

 black spots, or with more or less distinct traces of the livery of the 

 young ; a vertical black streak below the eye, and an oblique one 



