SNAKES. 



155 



hinder maxillary teeth longer and rather distant from the others. 

 On the other hand it is a connecting link between the Dendrophida 

 and the family of Dryiophidce, having the pointed snout and the 

 excessively slender habit of the latter. Its pupil is round. 



Fam. IX. DRYIOPHIDCE. 



Body generally excessively slender and elongate ; head very 

 narrow and long, with a thinly-pointed snout, sometimes ending 

 in a flexible appendix ; upper jaw much longer than lower ; 

 rostral shield always protruding, sometimes peculiarly modified ; 

 mouth deeply cleft ; nostril lateral, small ; eye rather small, with 

 an ovoid or linear, horizontal pupil (except in Dryiophis acumi- 

 nata, having a round one) ; one {Langaha two) anterior, one to 

 two {Langaha four) posterior orbitals; shields of crown regular 

 elongate ; scales very narrow, imbricate, scarce, in fifteen or seven- 

 teen rows {Langaha nineteen) ; those of the vertebral row gene- 

 rally broader, triangular ; ventral plates without or with obsolete 

 keels ; subcaudals two-rowed. Maxillary teeth sometimes (in the 

 Asiatic species) unequal, the fourth, fifth or sixth longer ; the 

 hinder one always longest and grooved. 



Dryiophis, Boie, Isis, 1827, p. 520; Schleg. Ess. ii. p. 241. 

 Oxycephalies, Dum. <y Bibr. vii. p. 79/. 



Synopsis of the Genera. 



1. Dryiophis. Muzzle pointed ; rostral solid. 



2. Passerita. Muzzle ending in a flexible appendage, not 



longer than one-third of head. 



3. Langaha. Muzzle ending in a flexible appendage, longer 



than one-third of head, covered with scales. 



1. Dryiophis, Boie. 



Head much elongated, pointed in front, but the front part 

 solid, not moveable. 



Tragops et Oxybelis, Dum. <y Bibr. pp. 813 & 822. Dryiophis, 

 sp., Boie, Isis, 1827, p. 520 ; Cuv. Reg. Anim. ; Schleg. Ess. ii. 

 p. 241. Oxybelis, Dryiophis et Tragops, sp., Wagl. Nat. Syst. der 

 Amph. pp. 183 & 184. Dryinus, sp., Merr. Tent. p. 136; Bell. 

 Zool. Journ. 1825. Natrix, sp., Coluber, sp., auct. prior. 



1. Dryiophis argentea. 



Coluber argenteus, Daud. Hist. Rept. vi. p. 336. Natrix 

 argentata, Merr. Tent. p. 116. Dryiophis argentea, Schleg. Ess. 

 t. 10. f. 14, 15. Oxybelis argenteus, Dum. cy Bibr. vii. p. 815. 



