iV APPENDIX. 



flattened tail; or to the Crotalidse or Viperidffi with erectile 

 tubular fangs and rough scales, and if to neither of these 

 groups, it still remains to determine whether it belongs to one 

 of the innocuous species which possess no loreal or to a poisonous 

 species, none of which possess it. The poisonous Elapidse are 

 all characterised by a small eye with a round pupil and by the 

 presence of a venom fang, grooved in front, and terminating in a 

 slit. There are only four genera, and if the snake under consi- 

 deration belongs to none of these, it is harmless, though no loreal 

 is present. The four genera of poisonous colubrine snakes are : 



Naja. 



Scsales round the body in 15 rows ; more numerous on the neck, 

 which is dilatable. There are only two species -. the Hamadryad, 

 N. claps, which has some of the anterior subcaudal shields single, 

 in other respects resembling a gigantic Cobra; and the Cobra, 

 N. tripudians, which is too well known to need description. 



BUNGAEUS. 



Scales rounS the body in 15 rows ; those of the vertebral series 

 enlarged. Subcaudal shields entire, all or some. The best known 

 and most dreaded species of this genus is the 'krait,' B cseruleus. 

 Colour brown or black with a blue iridescence, and generally 

 some narrow transverse white bars or markings across the back. 

 A second common species is the banded Bungarus, B fasciatus, 

 a large snake, alternately black and yellow banded, the ripgs 

 encircling the body. A closely allied species from Ceylon has 

 been specifically separated by Giinther. A fourth species only 

 found in Tenasserim (Borneo, Java, &c.) is B flaviceps body 

 black, head bright red, with a narrow vertebral red line ; and 

 some of the subcaudals bifid. 



Xenueelaps. 



The sole species of this genus is small and rare. It differs from 

 Callophis in having the vertebral rows of scales enlarged, and 

 scales in 15 rows. 



