482 BULLETIN 58;, UNITED STATES NATIONAL MUSEUM. 



enters the pit, two small scales, one above the other, two elongate 

 anterior preoculars, the upper, wliicli is somewhat wider anteriorly 

 turned up over the canthal ridge, the low^er forming the upper border 

 of the large pit; the subfoveal as large as the lower preocular, pos- 

 teriorly entering eye between the latter and the subocular; a long, 

 narrow, crescentic subocular anteriorly in contact with subfoveal, 

 separated from fourth and subsequent supralabials by one and pos- 

 teriorly two rows of scales; three small postoculars on left side, two 

 on right; temporals numerous, lower ones largest, upper ones smaller, 

 keeled; 10 supralabials, first small, triangular, second very high, 

 forming anterior border of pit, third largest, fourth slightly larger 

 than fifth to tenth, which are subequal; 3 lower labials in contact with 

 anterior cliin-sliields, posterior chin-shields scarcely differentiated; 

 21 rows of narrow, pointed, keeled scales without apical pits; 161 

 ventrals; anal entire; 69 pairs of subcaudals; tip of tail rather 

 blunt. Color (in alcohol) above saturated uniform "parrot-green;" 

 from the subocular, under the center of the eye, a narrow, strongly 

 defined, pale-yellowish line, the lower row of temporals and across 

 the last supralabial to the side of neck and from there to near the tip 

 of the tail on the middle line of the outer scale row, the lower edge of 

 which is somewhat darker than the rest of the body; underside 

 paler green, washed with blue so as to be almost "beryl-green" 

 toward the sides; tips of tail colored like the rest of the body. 



Dimensions. 



mm. 



Total length 618 



Snout to vent 488 



Vent to tip of tail 130 



The female appears to have a relatively much shorter tail. No. 2a, 

 Science College Museum, measuring 525 mm. in total length, has a 

 tail only 92 mm. long. 



Variation. — The Formosan specimens examined by me are very 

 uniform, both in scutellation and coloration, as will be seen from the 

 table at the end, but in individuals from all over the wide range of the 

 species there is displayed a corresponding range of variation. Thus, 

 19 and 23 scale rows are occasionally, though rarely, recorded; supra- 

 labials vary between 8 and 12, ventrals between 145 and 175, sub- 

 caudals between 53 and 75 pairs. The color variations consist in 

 more or less distinct blackish dorsal cross bands and the absence of 

 the lateral yellow line. The terminal portion of the tail is frequently 

 yellow or reddish, a color phase which until recently was regarded 

 as a distinct species under the name of Trimeresurus erythrurus. 



Ilahitat. — This species is widely distributed from the Himalayas in 

 the north and west, through India, Indo-China, southern China, to the 

 Malayan peninsula, Sumatra, Java, and Timor in the south, and 

 Formosa in the east. 



