226 » _ COLUBRID, 
two postoculars; temporals 1+1; seven upper labials, third and 
fourth entering ‘the eye; first lower labial in contact with its 
fellow behind the symphysial ; four lower labials in contact with 
the anterior chin-shields, which are longer than the posterior. 
Seales in 15 rows. Ventrals 111; anal divided. Pale brown 
above, speckled with darker; head and nape darker; whitish 
beneath. 
Total length 140 millim, 
British Honduras. 
a. d (V. 111; C.?). British Honduras O. Salvin, Esq. [P.]. 
(Type.) 
20. Homalocranium atriceps. 
Homalocranium atriceps, Giinth. Biol. C.-Am., Rept. p. 146, pl. lii. 
fig. B (1895). Ps, ’ ’ 
Eye not half as long as the snout. MRostral broader than deep, 
well visible from above; internasals half as long as the prefrontals ; 
frontal hexagonal, obtuse-angled in front, acute-angled behind, once 
and one third to once and a half as long as broad, longer than its 
distance from the end of the snout, shorter than the parietals; 
nostril between two nasals, the posterior in contact with or 
narrowly separated from the preocular ; two postoculars ; temporals 
1+1; seven upper labials, third and fourth entering the eye; 
first lower labial in contact with its fellow behind the symphysial ; 
four lower labials in contact with the anterior chin-shields, which 
are longer than the posterior. Scales in 15 rows. Ventrals 123- 
125; anal divided; subcaudals 55-59. Pale reddish brown above ; 
upper surface of head blackish, bordered behind by a whitish cross- 
bar ; lower parts white. 
Total length 170 millim. ; tail 47. 
North Mexico. 
a-b. 3 (V. 1238, 125; 0. 55, 59). Nuevo Leon. W. Taylor, Esq. [P.}. 
(Types.) 
21. Homalocranium planiceps. 
cae planiceps, Blainv. Nouv. Ann, Mus, iv. 1835, p. 294, pl. xxvii. 
Homalocranium planiceps, Dum. § Bibr. vii. p. 857 (1854) ; Jan, 
Arch, Zool, Anat. Phys. ii, 1363, Be Rent y Gén. he ‘pl. ii. 
fig. 2 (1866); Bocourt, Miss. Sc. tae 581, pl. xxxvi. 
(1895). 
fig. 7 (1883) ; Gtinth. Biol. C-dm., Rep 1 
Tantilla nigriceps, Kennicott, Proc. A hilad, 1860, p. 828; Cope, 
Proc. U.S, Nat. Mus. xiv. 1891, p. 598. 
Scolecophis fumiceps, Cope, Proc. Ac. Philad, 1860, p. 371. 
Tantilla planiceps, Cope, Proc. Ac. Philad. 1861, 3 74, and Proce. 
U.S. Nat, Mus. xiv. 1891, p. 597. 
Homalocranium ame Bocourt, Miss. Se. Mex., Rept. p. 582, 
pl. xxxvi. fig. 
Eye not half as long as the snout, which is much depressed and 
