184, HOMALOCRANIUM. 215 
TABLE SHOWING NuMBERS OF SHIELDS. 
Vv. 0. Postoe. Lab. 
melanocephalum ..screrereeeeee 133-171 46-71 2 7 
ANNULALUIM ....ccccecees- svoeees 149 54 2 ” 
Erilineatum ...-ccccscecsescecces 145-163 68-69 2 8 
longifrontale ....0..e.sseeee eee 158 85 2 < 
COT ONALMM aaciakiaidevivancvsdtees 138-158 40-58 2 yj 
PUOLUM ccd aewenenietsss<ccnad 149-179 59-70 2 7 
SCEMBMENCLUME |.cccsecssecsssesces 143-180 50-72 2 7 
fusdae 0 leee ess scien 136-159 44-49 2 7 
BOUlENGers ...srcccreessceecrsenses 161 46 2 7 
SCHISCOSUME —. .cnccseccescescecees 121-1385 32-38 2 7 
CONIC: |. cheetah dasudcennnseanenede 110 37 2 | 
GEM ATUNE TF pas iin cssanpapeia ness 147-152 5d 2 7 
VirgaluM LMis.ss.scidedaaglias. 154-175 57-65 2 7 
PUOOIS nk. ods g0n si taxa os kia 146 ? 2 7 
ae ere Dee ee 172-176 55 2 7 
POCCULATUM oon ccsseccecsccvecess 148 67 2 ‘4 
ee ee ears a aaa 140-148 55-63 2 7 
WEY INAZOYINE 60 c.csecsrescrresscs 122 26 2 7 
DE atin cabs sos sacchaar-socenss 111 ? 2 7 
MRED ate) 52 sean gsbenees «ses 123-125 55-59 2 7 
MOMMOIE Mos. Lob bess 5 <cn0sedeseee 121-153 42-58 1-2 7 
CALAMATINUM — acesececcccsceees 119-132 27-35 1 6 
IIR Eiciercdennvsvncatonsansesci 112-133 41-51 1 6 
1. Homalocranium melanocephalum. 
Coluber melanocephalus, Zinn. Mus. Ad. Frid, p. 24, pl. xv. fig. 2 
(1754), and 8. N. i. p. 378 (1766). 
Elaps melanocephalus, Wagl. in Spix, Serp. Bras. p. 8, pl. ii. 6. fig. 1 
1824). 
Duberria melanocephala, Fitzing. N. Class. Rept. p. 55 (1826). 
Cloelia dorsata, Wagl. Syst. Amph. p. 187 (1830). 
Calamaria melanocephala, Schleg. Phys. Serp. li. p. 38, pl. i. fig. 30 
(1837) ; Zrosch. in Schomb. Reise Brit. Guian. iii. p. 652 (1848). 
Homalocranium melanocephalum, Dum. § Bibr. vii. p. 859 (1854) ; 
Bocourt, Miss. Sc. Mex., Rept. p. 588, pl. xxxvii. fig, 4 (1883). 
melanocephalum, part., Giinth. Cat. p. 18 (1858); Jan, Arch. 
Zool, Anat. Phys. ii. 1862, p. 51, and Icon. Gén. 15, pl. ii. fig. 5 
(1866) ; Giinth. Biol. C.-Am., Rept. p. 147 (1895). 
Tantilla melanocephala, Cope, Proc. Ac. Philad. 1861, p. 74, and 1868, 
. 102. 
Elapomorphus mexicanus, Giinth. Ann. § Mag. N. H. (8) ix. 1862, 
p- 57, pl. ix. fig. 1. 
Tantilla melanocephala, part., Cope, Proc. Ac. Philad. 1866, p. 126. 
capistrata, Cope, Journ. Ac. Philad. (2) viii. 1876, p. 181. 
Homalocranium melanocephalum, vars. fraseri and pernambucense, 
Giinth. Biol. C.-Am. p. 148. 
armillatum, part., Giinth. 1. c. p. 149, pl. lii. fig. C. 
mexicanum, Giinth, 1. e. p. 153. 
Eye about half as long as the snout. Rostral much broader than 
deep, visible from above ; internasals not more than half as long as 
