82. UROTHECA. 183 
Liophis tricinctus, Jan, Arch. Zool. Anat. Phys. ii. 1863, p. 301, and 
Icon. Gén. 18, pl. iv. figs. 4-6 (1866). 
Pliocercus dimidiatus, Cope, Proc. Ac. Philad. 1865, p. 190, and 
Journ. Ac. Philad. viii. 1876, p. 188, and Proc. Amer. Philos. Soc. 
xxii, 1885, p. 183. 
sargii, Fisch. Arch. f. Nat. 1881, p. 225, pl. xi. figs. 1-3. 
Liophis elapoides, Garm. N. Am. Rept. p. 69 (1883) ; Bocourt, Miss. 
Sc. Mex., Rept. p. 635, pl. xli. fig. 6 (1886). 
elapoides, vars. diastema e¢ equalis, Bocourt, l.c. figs. 7 & 8. 
Elapochrus equalis, Giinth. Biol. C.-Am., Rept. p. 106, pl. xxxvi. 
tig. A (1893). 
—— dimidiatus, Giinth. 1. c. p. 107. 
Eye rather small; snout short, rounded. Rostral nearly twice 
as broad as deep, just visible from above; internasals shorter than 
the prefrontals; frontal as long as or a little longer than its 
distance from the end of the snout, shorter than the parietals ; 
loreal as long as deep ; one or two preoculars and asmall subocular ; 
two postoculars ; temporals 141 (rarely 1+2); eight (rarely nine) 
upper labials, fourth and fifth (or fifth and sixth) entering the eye ; 
five lower labials in contact with the anterior chin-shields, which 
are a little longer than the posterior. Scalesin 17 rows. Ventrals 
124-148; anal divided ; subcaudals 85-127. Red above, the scales 
usually tipped with black, with single or triple black annuli, the 
annuli when triad separated by yellow interspaces ; some large black 
spots may be present on the red areas; head black in front and 
behind, with a yellow band across the parietal shields and the 
temples ; belly yellowish between the rings. 
Total length 550 millim.; tail 240. 
Mexico, Guatemala, Costa Rica. 
The individuals of this species vary immensely in the number and 
arrangement of the annuli, as may be seen by referring to the 
descriptions and figures quoted in the synonymy. I am therefore 
disposed to regard the forms diastema (5 triad annuli on the body) 
and equalis as extreme colour-varieties of one species. I have dealt 
in the same manner with Atractus elaps and A. latifrons, which 
present analogous variations. 
A. Black annuli triad, with yellow interspaces. 
a. 7 to 10 annuli on the body ; irregular black blotches on the 
red areas. 
a. 3 (V. 126; C. 97). Mexico. 
ba (V.128;.C. ?). Teapa, Tabasco. F. D.Godman, Esq.[P.]}. 
ce. 9 (V. 183; C.110). Jalisco. F.D. Godman, Esq. | P. |. 
6. 8 annuli on the body; no black spots. 
d. Ye. (V.130; C. 104). Duenas,Guatemala. O. Salvin, Esq. ieee 
B. 25 to 27 equidistant black annuli on the body. 
© (V. 183; C. 92). S.Gerdénimo, Guate- Robert Owen, Esq. [C. ]. 
mala. (Type of P. equalix.) 
f. Yg. (V. 181; C. 112). Vera Paz,low forest. O. Salvin, Esq. [C.]. 
Ss 
