276 COIUBEIBJI, 



■^ 5. Helicops trivittatus. (Plate XVIIl. fig. 2.) 



Myron trivittatus, Oray, Cat. p. 70 (1849). 



Eye small. Eostral mucli broader than deep, visible from 

 above ; nasals usually in contact behind the rostral ; frontal about 

 twice as long as broad, as long as its distance from the end of the- 

 snout, shorter than the parietals ; loreal deeper than long ; two prae- 

 and two or three postoculars; temporals 1+2 ; eight upper labials^ 

 lourth entering the eye ; five lower labials in contact with the an- 

 terior chin-shields, which are nearly as long as the posterior. Scales- 

 faintly keeled, in 21 or 23 rows. Ventrals 120-130 ; anal divided; 

 subcaudals 63-65. Coloration very much as in Ahasior erythro- 

 grammus. Dark olive above, with small black spots and five yel- 

 lowish or reddish longitudinal streaks, outer widest; belly yellow or 

 orange, with two regular longitudinal series of subcresceiitie trans- 

 verse black spots. 



Total length 670 millim. ; tail 190. 



Brazil. 



a. 2 (V. 126 ; C. 63). ? Zoological Society. (Type.) 



b. cJ (V. 120 ; C. ?). ? Zoological Society. 



c-d. Yg. (V. 130, 129; Para. R. Graham, Esq. [P.]. 



C. 65, 65). 



/ 6. Helicops carinicauda. 



Coluber carinicaudus, TVied, Beitr. Nat. Bras. i. p. 800 (1826), and 



Abbild. (1826). 

 Helicops carinicaudus, Wagl. Icon. Amph, pi. -^ii. (1828) ; Bvm. i^ 



Bibr. vii. p. 744 (1854) ; Jan, Arch. Zool. Anat. Phys. iii. 1865, 



p. 262 ; Hensel, Arch.f. Nat. 1868, p. 3l'9 ; Bouleng. Ann. 8^ Mag. 



N. S. (5) xvi. 1885, p. 297, and xviii. 1886, p. 435. 

 Homalopeis carinicaudus, Schkg. JPhys. Serv. ii. p. 350, pi. xiii, 



tigs. 17 & 18 (1837). 

 Helicops carinicaudus, var. gastrosticta, Jan, I, c. 

 infrateeniatus, Jan, A rch. Zool. Anat. Fhys. iii. 1865, p. 245, and 



Icon. Oen. 28, pi. iii. tig. 3 (1868) ; Cope, Proc. Am. Philos. Soc. 



xxii.1885, p. 193. 



■ trivittatus. Cope, Proc. Am. Philos. Soc. xvii. 1877, p. 92. 



baliogaster, Cope, Proc. Am. Philos. Soc. xxii. 1885, p. 193. 



Eye small ; rostral visible from above, forming a narrow suture 

 with the internasal ; frontal twice as long as broad, widening pos- 

 teriorly, much longer than its distance from the end of the snout, 

 as long as or a little shorter than the parietals ; loreal deeper than 

 long (rarely absent); one prae- and two postoculars ; temporals l-|-2 

 or 2-1-2; seven or eight upper labials, third or fourth (rarely third 

 and fourth) entering the eye ; four or five lower labials in contact 

 with the anterior chin-shields, which are as long as or a little 

 shorter than the posterior. Scales in 19 rows, feebly keeled 

 anteriorly, strongly keeled on the posterior part of the body and on 

 the tail ; outer scales smooth. Ventrals 1:^6-155 ; anal divided j 



