MORPHOLOGY OF VENOMOUS SNAKES 37 



Ancistrodon intennedius. 



Ancistrodon blomhoffii intermedius Stejneger. 



About same as halys except that the snout is not turned at the end. Length 

 about 2.5 feet. Central Asia, eastern Siberia, Mongolia, and Japan. 



Ancistrodon blomhoffii.i 



Resembles the halys, but not turned up on end of snout. Coloration variable: 

 gray, brown, or red above, with large black-rimmed blotches in pairs; black bands 

 with red margin; belly yellow or reddish, more or less spotted black. Length 

 about 2.5 feet. Japan, Mongolia, eastern Siberia, central Asia. 



Ancistrodon blomhoffii brevicaudus - Stejneger. 



Much like Ancistrodon blomhoffii of Japan, but is distinguished from it by ab- 

 sence of white spot at anterior angle of crescentic lower postocular, and by the 

 fewer number of subcaudals. Length about 2 feet. Eastern China, Korea, and 

 Formosa. 



Ancistrodon himalayanus. 



Snout hard, markedly turned upwards. Color brown with black crossbars or 

 points; a light-margined black band from eye to the angle of mouth; belly dark 

 brown or more or less whitish. This snake lives chiefly on mice. Length about 

 2 feet. Himalayas up to 10,000 feet, especially in the northwest. 



Ancistrodon acutus. 



The snout is so prolonged as to protrude. Length about 5 feet. Upper Yang- 

 tse, China. 



Ancistrodon rhodostoma. 



Snout pointed, sometimes directed upwardly. Length about 3 feet. Java. 

 Ancistrodon hypnale. (Plate 14, A.) 



Snout more or less curved, with a hard-pointed end. Scales in 17 (most of the 

 Ancistrodon species 21) rows. Length about 2 feet. It is known as "carawalla" 

 in Ceylon, where it is dreaded. Ceylon, western coasts of India to Bombay. 



Genus LACHESIS Daudin.s (Plate 15, A.) 



Without a rattle, but the tail has a series of 10 to 12 rows of spinous scales sharp- 

 ened at end. Head covered with plates or small smooth or carinated scales, with or 

 without special fossa. Maxillary bone much reduced in dimensions, but ectoptery- 

 goid is well developed. The absence of the regular shields on top of head makes 

 it easy to differentiate this genus from Ancistrodon. Many species of Lachesis 

 of Asiatic origin are called Trimeresurus. Stejneger points out that it has not 

 been conclusively demonstrated that they are generically identical with the numer- 

 ous American pit-vipers of a similar head scutellation, which are usually known 

 as Trigonocephalus or Bothrops. The South American Lachesis is sufficiently 

 characterized by the peculiar scutellation of the tail. 



The American representatives of Lachesis are as follows: 



Lachesis lanceolatus. 



Known as Fer de lance of Martinique, " Jararacussu " of Brazil, and Bothrops 

 lanceolatus of various authors. Snout obtuse, slightly elevated; scales of top of 

 head are small and imbricated, more or less strongly carinated. Subcaudal in two 

 rows. Coloration very variable: gray, brown, yellow, olive, or reddish, uniform or 



1 Mamushi. According to Stejneger this species is restricted to Japan, including the small southern 



islands. 

 * Ancistrodon blomhoffii affinis Gray was described, but its locality is uncertain; it is supposed to come 



from Yaeyama Island of RiuKiu, Japan. ■ ^ 



^Bothrops, Trigonocephalus, a.nd Trimeresurus are synonyms for this genus. 



