386 BULLETIN 58, UNITED STATES NATIONAL MUSEUM. 



Family ELAPID^. 



This family contains all the so-called "proteroglyph" snakes, or 

 snakes with a permanently erect grooved poison fang in the anterior 

 portion of the horizontal maxillary bone. 



The members of the family are divided into two snbfamilies, one 

 containing the terrestrial species which have retained the general 

 physiognomy of the majority of snakes, the other embracing forms 

 which have become strongly modified for marine life, as follows: 



«' Tail cylindric Elapin.ts, p. 386. 



a- Tail strongly compressed, oar-shaped Hydrin,« p. 400. 



Subfainily EIL.AFI]Sr.^:. 



As stated above, the general physiognomy of these snakes is that 

 of the great majority of snakes, the Natricidx, and the resemblance 

 of some of the species in each family is so complete as to have deceived 

 experts on a superficial examination. The generally small eye with 

 vertical pupil, frequent absence of a loreal, and even width of head 

 with body will serve to characterize many of the Elapines, but the 

 presence of the poison fang is the only reliable criterion. 



It is the more to be regretted that these snakes can not be readily 

 and at a glance distinguished from the numerous harmless species, 

 as they are the deadliest and often the most dangerous of all snakes. 

 Thus the Indian cobra, found in Formosa, and the so-called hama- 

 dryad belong to this subfamily. The "krait,". which grows to be 

 over 4 feet, and which is represented by a separate form in For- 

 mosa {Bungarus niulticinctus) is also very destructive of life where 

 it is common. On the other hand, the smaller species, although their 

 poison in proportion is equally deadly, are not very dangerous to man, 

 partly because of the smallness of their mouths, partly, it seems, 

 because of the supposed gentleness of some of them. 



The Elapine snakes are truly tropical in their distribution. Only 

 one genus, Elaps, occurs in America, wliile on the other hand the 

 majority of the Australian snakes belong to this family. 



Only four species, belonging to four genera, come within our limits, 

 viz, three in Formosa and one in the Riu Kins, although it would not 

 be surprising if additional species were discovered in the former island. 



They may be distinguished as follows : 



KEY TO THE FORMOSAN AND RIU KIUAN GENERA. 



a^ Median dorsal scale row not enlarged; subcaudals all, or mostly, in pairs. 



h^ Neck not (lilatal)le, not surrounded by more scale rows than niiddlc of body; 

 internasal not bordering the nostril. 



c' One to three small teeth on maxillary ))ehind fangs Iltviibiouidnis. j). 387. 



c- No teeth on maxillary behind fangs CaUiophis, p. 391. 



b'^ Neck dilalal)le; more scale rows around neck tlian uround michlle of luuly; inter- 

 nasal ])ordering the nostril Axya, p. 394. 



a- Median dorsal scale row enlarged; subcaudals single Bunyarus, p. 397. 



