NATURAL SCIENCES OF PHILADELPHIA. 77 



72. S. bifasciatus D. fr B. vii. 520. In this species the carina? are 

 very strong, and present on every row of scales. It is of a slender, elongate 

 form as mentioned by its describers, resembling the species of Ablabes in its 

 proportions. For this reason we question the propriety of removing this 

 genus from the neighborhood of Ischnognathus, where Dumeril places it, and 

 it is only the Calamarian form ofS. atratus that induces us to consent to 

 the position assigned by GLinther. Our specimens of species being fresh, we 

 will note : that the superior surface is not properly black, but deep slate ; and 

 that the collar and inferior labial plates are light yellow. The black upon the 

 gastrosteges covers an extent rather wider than each white lateral band. 

 Three specimens, Jalapa, Mexico, Sr. Rapfhael M. De Oca. 

 One " " Mr. Pease. 



Tantilla Bd. & Grd. Type T. coronata. 



Catalogue Serp., p. 131. 



This genus appears to be quite distinct from Rhabdosoma D. B., be- 

 ing characterized by a more slender body, longer tail, divided anal, and a 

 loreal plate, either united to the postfrontals or wanting. The latter two 

 peculiarities also distinguish it from Rhabdion D. Sf B. Posterior maxil- 

 lary teeth equal to the anterior, smooth. Perhaps Rhabdosoma elaps 

 Gthr. 1. c. 241, belongs here ; its anal scute is, however, entire. 



73. T. Hall owe 11 i nob. Tantilla gracilis Hallow., Proc. Acad. Nat. 

 Sci. viii. p. 246. 



This species is accurately described as cited, and the differences between it 

 and T. gracilis pointed out. These, we think, are of specific value, and 

 accordingly name it after Dr. Hallowell, as a slight recognition of his many 

 valuable contributions to herpetology. 



The form of this species is more like that of Haldea s t r i a t u 1 a B. * G., 

 than Carphophiops amoena. The locality, "Indianola, " assigned by 

 Dr. Hallowell, is probably a mistake, being copied from Baird & Girard's 

 Catalogue. We have one specimen brought from Kansas by Dr. Hammond. 



74. T. reticulata nob. Vertical plate broad, slightly angular in front, 

 projecting posteriorly for half its length between the occipitals. Occipitals 

 and both pair of frontals rather broad. Rostral broad, visible from above. 

 Nostril in the posterior part of prenasal ; postnasal in contact with first and 

 second superior labials, preocular, post- and prefrontals. Two postoculars, 

 upper one in contact posteriorly with the occipital, the lower touching one 

 temporal. A second temporal equal to the first, and a third very small one 

 behind it. Superior labials, seven last largest, third and fourth entering the 

 orbit both low. Four geneials, anterior in contact with inferior rostral. 

 Scales in fifteen rows, last one slightly larger. Gastrosteges 148, postab- 

 dominal 1 divided, urosteges 67 pair. Total length 10 in. 3 1. ; tail 3 in. 



Color above chestnut brown, much darker posteriorly, extending upon the 

 tips of the gastrosteges. Anteriorly the scales are edged with darker, pre- 

 senting a reticulated appearance. Central dorsal row of scales lighter, form- 

 ing a pale vitta, disappearing on the tail. Third and fourth rows on each side 

 also lighter, forming indistinct bands. A collar of the same pale yellow brown 

 crosses the ends of the occipitals. Cephalic plates clouded and edged with 

 darker ; a deep brown mark extending from the occipitals to the mouth across 

 the yellowish labials. Beneath pale yellow, deepening posteriorly. 

 One specimen, Cocuyas de Veraguas, New Grenada, R. W. Mitchell. 



This species seems to be much like the T. c o r o n a t u m B. $ G., but has 

 a much longer tail, and broader head-shields ; the upper post-ocular, not the 

 lower, is in contact with the temporal in the latter. See Pacif. R. R. Report, 

 x. Reptiles, pi. 38, fig. 96. 



I860.] 



