86. nvDRors. 187 



divided nasal ; a single internasal ; no loreal. Eodj cylindrical, 

 slender; scales short, smooth, without apical pits, in 15 or 17 rows; 

 ventrals rounded. Tail rather short ; subcaudals in two rows. 

 South America. 



1. Hydrops triangularis. 



Elaps triangularis, War/l. in Spi.r, Serp. Bras. p. 5, pi. 2«. fig. 1 (1824). 

 Ilomalopsis martii, Schleg. Phys. Serp. ii. p. 356, pi. xiii. figs. 19 & 20 



(1837). 

 Hydrops martii, Gray, Zool. Misc. p. 68 (1842), and Cat. p. 75 (1849) ; 



Dimi. Sf Bibr. vii. p. 484 (1854) ; Giinth. Ann. ^ May. N. H. (4) 



i. 1868, p. 421. 

 Iligina fasciata, Gray, II. cc. pp. 67, 75. 

 Calopisma martii, Jan, Arch. Zool. Anat. Phys. iii. 1865, p. 242, and 



Icon. Gen. 29, pi. iv. fig. 1 (1868). 



Snout broadly rounded. Rostral much broader than deep, scarcely 

 visible from above ; nasals in contact with each other behind 

 the rostral ; internasal rhomboidal, nearly twice as broad as long ; 

 frontal a little longer than broad, as long as or longer than its dis- 

 tance from the end of the snout, shorter than the parietals ; one 

 prse- and two postoculars ; temporals 1 + 1 ; eight upper labials, 

 fourth entering the eye ; four lower labials in contact with the 

 anterior chin-shields, which are as long as or shorter than the 

 postei-ior. Scales in 15 rows. Yentrals 145-176 ; anal divided ; 

 subcaudals 40-66. Purplish brown above, red on the sides, white 

 below : with black annuli, which may be interrupted and alternate 

 on the middle dorsal and ventral lines. 



Total length 780 millim. ; tail 110. 



Guianas, Brazil. 



a-b, c-e. Hgr. (V. 165, Demerara. (Types of ^. /«.<«'«<«.) 



170, 168, 176, 168; C. 



56, 58, ?, 56, 54). 

 /. Yg. (V. 167 ; C. 46). Demerara. Zoological Society. 



q-i. $ (V. 169, 161, 166; Berbice. 



C. 45, 43, 45). 

 k. Ilgr. (V. 160 ; C. 64). Surinam. W. Carruthers, Esq. [P.]. 



I. Yg. (V. 175; C. 42). Surinam. 

 m, n. Hgr. (V. 159; C. 60) ? 



&yg. (V. 157; C. 58). 



2. Hydrops martii. 



Elaps martii, Wagler, in Spix, Serp. Bras. p. 3, p]. ii. fig 2 (1824). 

 Hydrops callostictus, Giinth. Ann. ^ May. N. H. (4) i. 1868, p. 421, 

 pi. xvii. fig. B. 



Yery closely allied to the preceding, but scales in 17 rows. Ven- 

 trals 168-179; subcaudals 71-76. lied, back purplish, with black 

 annuli, which are bordered on the upper surface of the body with 

 round whitish spots. 



Total length 265 millim. ; tail 60. 



Brazil and N.E. Peru. 



a. ITgr. (V. 168; C. 71). Chyavetas, Upper Mr. E. Bartlett [C.]. 



Amazon. (Type of //. callostictus.) 



