184. HOMAIOCEANIUM. 217 



Tantilla pallida, Cope, Proc. Amer. Philos. 800. xxiv. 1887, 

 p. 56, from Matto Grosso, Brazil, appears to agree in every respect 

 with H. melanocephalum, except in having the first lower labial 

 separated from its fellow by the symphysial. This is probably 

 merely an individual variation, as the condition described by Cope 

 is nearly attained by two of the specimens from Para in the 

 Museum. 



2. Homalocranium annulatum. 



Tantilla annulata, Boettg. Zool. Ann. 1892, p. 419. 

 Homalocranium annulatum, CHinth. Biol. C.-Am., Rept. p. 160 

 (1895). 



The description does not give any structural characters by which 

 this form may be distinguished from H. melanocepJialum, but the 

 coloration is very different. Head black ; snout to the middle of 

 the praefrontals yellow ; fifth upper labial yellow ; two narrow yellow 

 collar-bars, each broadly edged with black, the anterior crossing 

 the extremity of the parietal shields ; anterior third of body dark 

 grey-brown, with alternating yellow, black-edged transverse spots 

 or bars extending from the vertebral line to the outer ends of the 

 ventrals ; lower parts uniform yellow. 



Total length 484 millim. ; tail 99. 



Nicaragua. 



3. Homalocranium trilineatum. 

 Leptocalamus trilineatus, Peier«, Mon. Bert. Ac. 1880, p. 221, pi.—. 



fig. 2. 

 Homalocranium tseniatum, Bocourt, Miss. Sc. Mex., Mept. p. 587, 



pi. xxxvii. fig. 3 (1883) ; Ounth. Biol. C.-Am., JRept. p. 151 (1895). 

 trivittatum, F. Mull. Verh. Nat. Ges. Basel, vii. 1885, 



p. 678. 

 Tantilla tseniata, Cope, Bull. U.S. Nat. Mus. no. 32, 1887, p. 83. 



Eye half as long as the snout. Eostral much broader than deep, 

 visible from above; internasals half as long as the prsefrontals ; 

 frontal hexagonal, obtuse-angled in front, aoute-angled behind, 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 the prseocular ; two postoculars ; tem- 

 porals 1-1-1 ; eight upper labials, third and fourth entering the eye; 

 first lower labial separated from its fellow, the symphysial being m 

 contact with the anterior chin-shields; four lower labials m contact 

 with the anterior chin-shields, which are longer than the postenor. 

 Scales in 15 rows. Ventrals 145-163; anal divided; subcaudals- 

 68-69. Brown above, with three yeUowish, dark-edged longitudinal 

 lines; a yellowish cross-band on the occiput, not connected with 

 the longitudinal lines ; a yeUowish spot on each side ot the head 

 behind the eyes ; lower parts whitish. 



Total length 275 millim. ; tail 65. 



Guatemala, Honduras. 

 a. S (V. 163 ; C. 69). Bonacca Id., Honduras. F. D. Godman, Esq. 



