NATURAL SCIENCES OF PHILADELPHIA 341 



One specimen in alcohol, sent to the Smithsonian Institution, from Charlotte 

 Harbor, Florida, by E. M. Baker. 



T. celaeno Cope. 



Scales in nineteen or twenty-one rows, all carinate except the first. Head 

 broad and distinct posteriorly, constricted at the orbits, and remarkably nar- 

 row anteriorly. Profile of the crown slightly, but regularly convex. Super- 

 ciliary plates narrow and elongate. Vertical elongate, its lateral borders 

 concave, not convergent posteriorly, its length greater than that of the occipi- 

 tal suture. Frontals small, the anterior almost triangular. Nasals and loral 

 rather large, the posterior border of the latter very oblique. Preocular one, 

 postoculars three. Superior labials eight, eye resting on the fourth and fifth, 

 sixth and seventh largest and bounded above by the first temporal. Remain- 

 ing temporals four on each side. Inferior labials ten, sixth longest. Posterior 

 geneials longer than the anterior. General form rather slender, tail one-fifth 

 the total length. Gastrosteges 145 ; one divided anal ; urosteges 71. 



Coloration. The general hue is leaden black above and below, with the 

 following paler markings. A band of leaden gray commences upon the neck, 

 occupying the second, third, and part of the first rows of scales. This ex- 

 tends to the anus, becoming darker, and leaving the first row of scales poste- 

 riorly. Upon the anterior third of the body irregular narrow vertical bands 

 extend from this, separated by black spaces of one and a half or two scales 

 in width, which spaces are sometimes enclosed by the confluence of the bands 

 on each side of the black vertebral line. 



One specimen (No. 351,) discovered by Mr. John Xantus, at Cape St. Lucas, 

 Lower California, and deposited in the Museum of the Smithsonian Institute. 



This species may be distinguished from those called Eutaenia, by Baird and 

 Girard, by its divided postabdominal scutellum. It, however, bears quite a 

 close resemblance to some of them, e. g., E. P i c k e r i n g i i . It is^unneces- 

 sary to institute any comparisons with our true Tropidonoti, (which possesses 

 the divided scutellum,) it is so strikingly different from all of them. 



T. TEPHROPLEURA Cope. 



Scales in nineteen or twenty-one longitudinal rows, keels obsolete on the 

 external series only ; second row larger than those of the back. Head distinct, 

 narrow anteriorly, its lateral outlines regularly converging from the canthus 

 of the mouth. Outline of the crown slightly depressed behind the plane of 

 the orbits. Head shields much elongated, especially the superciliaries and 

 vertical, the latter twice as long as wide. The lateral borders do not converge, 

 and the posterior angle is but little greater than a right angle. Nasals large ; 

 loreal as high as long ; two pre-, three postoculars, the former partially 

 united in an old individual. Superior labials eight, sixth much the largest, 

 its superior border and two-thirds of that of the seventh in contact with the 

 very large first temporal. Remaining temporals normally four, sometimes 

 confluent in pairs. Inferior labials ten, sixth the longest. General form 

 stout ; tail one-fourth of the total length. Gastrosteges 146 ; one divided 

 anal; urosteges 83. Total length 32 inches, tail 8 in., 31.; of a larger speci- 

 men, 9 in., 8 1., and the total length 38 in. 31. 



Coloration. Above plumbeous brown, shading into plumbeous grey or ash 

 upon the sides, which color fades into pale greyish yellow upon the middle of 

 the belly. Urosteges ashy, with a dark shade along the central suture. When 

 the skin of the upper part of the body is stretched, it is seen to be leaden black 

 along the medial line, with two or three series of quadrate spots of the same 

 color on each side. These spots usually alternate, but are sometimes conflu- 

 ent into oblique bands. 



Two specimens (4681 type, and 4680,) in the museum of the Smithsonian 

 Institution, Washington, discovered at Cape St. Lucas, in Lower California, 

 by Mr. John Xantus. 



I860.] 23 



