HERPETOLOGY OF JAPAN. 265 



the province of Fokien, opposite Formosa, as the nearest relatives 

 known. Bearing in' mind that the relative size of the posterior 

 maxillary teeth is of little practical importance, I thmk we may also 

 safely add to this group Natrix cJirysarga, a species which extends 

 from the eastern Himalayas to southern China, the Indo-China penin- 

 sula, and the Malay Ai'chipelago. As will be shown further on, Natrix 

 pryeri is a specialized member of this group. From what w^e now 

 know of the distribution and relationship of the other reptiles in 

 these regions, it is pretty safe to predict that a Natrix of the same 

 group, either N. craspedogaster, or N. cJirysarga, or a form intermediate 

 between one of these and N. pryeri, will be found to occur in Formosa 

 when the herpetological fauna of this island shall have become thor- 

 oughly known." 



The other species enter our territory only in Formosa and as such 

 their Himalayo-Chinese relationships are easily traced. Both N. 

 stolata and TV. piscator occur from the Himalayas and India to 

 southern China, Indo-China, and the Malayan Islands. N. annularis 

 also mhabits the Yangtse drainage and N. stvinhonis has its nearest 

 relative, N. nuchalis, located on the upper Yangtse Kiang. 



KEY TO THE JAPANESE, KOREAN, AND FORMOSAN SPECIES OF NATRIX. 



a' Scale rows, 19; supralabials, 7, 8, or 9. 

 ¥ Subcaudals less than 105 pairs. 



c' Suture between rostral and internasal not shorter than between rostral and first 

 supralabial (fig. 241). 



d} Parietals longer than distance from eye to tip of snout N. vibakari, p. 266. 



<P Parietals equaling the distance from eye to tip of snout. 



e^ Ventrals plus subcaudals more than 226; subcaudals more than 65. 



N. tigrina, p. 272. 

 e- Ventrals plus suljcaudals less than 226; subcaudals less than 65. 



N. tigrina lateralis, p. 278. 



a NATRIX CHRYSARGA (Schlegel). 



1837. Tropidonotits chrysargos Schlegel, Phys. Serp., II, p. 312 (type-locality, 



Java; types in Leiden Mus.; Kuhl and Reinwardt, collectors). 

 1847. Tropidonotus junceus Cantor, Cat. Mai. Rept. (p. 93) (type-locality, Pinang; 



type in Brit. Mus.; Cantor, collector). 

 1868. Ainpkiesma platyceps jAti, Icon. Ophid., livr. 29, pi. ii, fig. 1 (type-locality, 

 Sikkim; type in Milano Mus.) (not Tropidonotus platyceps Blyth, 1854). 

 Scale rows, 19, all strongly keeled; 9 or 8 supralabials; 60-93 pairs of subcaudals; 

 suture between rostral and internasal not shorter than between rostral and first supra- 

 labial; parietal longer than distance from eye to tip of snout; 2 anterior temporals. 



NATRIX CRASPEDOGASTER (Boulenger). 



1899. Tropidonotus craspedogaster Boulenger, Proc. Zool. Soc. London, 1899, p. 

 163, pi. XVII, fig. 1 (type-locality, Kuatun, prov. Fokien China; types in 

 Brit. Mus.; La Touche, collector). 

 Scale rows, 19, outer faintly keeled; 8 supralabials; 87-97 pairs of subcaudals; 

 anterior temporals 1 or 2 (from original description). 



