I So 

 38. Hypsirhina Wagler. 



(Wagler, Syst. Amph. 169, 1830). 



Head small, not or slightly distinct from neck; eye small; 

 pupil round or vertically elliptic; shields of head large; nasals 

 in contact, partly divided, the cleft beginning at the first 

 labial or the loreal; internasal single or double; loreal present. 

 Maxillary teeth 10 — 16, separated by an interspace from two 

 enlarged, grooved teeth; anterior mandibular teeth longest. 

 Body round, covered with smooth scales without pits, in 

 19 — 33 rows; ventrals rounded. Tail rather short; subcaudals 

 in two rows. 



Distribution. S. E. Asia; Papuasia; N. Australia. 



Key to the I n d o-A u st r al i an species. 



^. One or more labials entering the eye. 

 I. Scales in 19 rows. 



a. Two internasals I. //. alternans p. 180. 



b. A single internasal 2, H. phimbea p. 181. 



II. Scales in 21 (23) rows. 



a. Four or five lower labials in contact with 

 the anterior chin-shields. 



1. Loreal in contact with the internasal. 3. H. enhydris p. 181. 



2. Loreal not in contact with the internasal. 4. H. matannensis p. 182. 



b. Three lower labials in contact with the 



anterior chin-shields S- H. polykpis p. 183. 



III. Scales in 27 (25) rows 6. H. albomaculata p. 183. 



B. Eye separated from the labials. 



1. Internasal single • "]. H. ptiiiclala p. 1 84. 



2. Two internasals 8. //. Joriae p. 185. 



I. Hypsirhina alternans (Reuss). 



Brachyorrhos alternans^ Reuss, Mus. Senckenb. I 1834, p. 155, pi. IX, fig. 3. 

 Hypsirhina alternans^ Boulenger, Cat. Sn. Ill 1896, p. 4 (s. syn.). 



Rostral more broad than deep; two internasals; frontal 

 broader than the supraocular, as long as or longer than its 

 distance from the tip of the snout, shorter than the parietals; 

 loreal as long as deep, in contact with the internasal; one 

 prae- and one or two postoculars; temporals i + 2; eight upper 

 labials, fourth entering the eye; four or five lower labials in 

 contact with the anterior chin-shields, which are larger than 



