CROCODILIANS, LIZARD8, AND SNAKES. 499 



Body slender, contained two and one-third times in tlie tail; dorsal 

 scales in fourteen longitudinal series; ventral in ten; and one hundred 

 and twenty from head to anus. The carination of the dorsal scales is 

 conliued chiefly to the two median rows, although it is obsoletely visi- 

 ble on ten rows on each side of these. There is a conspicuous broad, 

 but shallow groove along the back between these ten median cariuse. 

 Tlie head is very narrow, as high as broad. 



The ground color is a light olive green, or greenish gray above, with 

 a median and five lateral (on each side) nearly equal stripes of dark 

 brown (or sides brown with four narrow white lines). The median 

 occupies the space between the dorsal carinte. Then comes an olive 

 strii)e of If rows, and then a brown stripe. For the rest of the lateral 

 series there is a narrow, well-defined stripe of whitish in the central 

 fifth; tlie space between these lines is brown. These markings are 

 equally distinct on the tail, which has the stripes continued a little 

 below the level of those on the sides, though continuous with those 

 above the lateral groove. Near the head the dusky lateral stripes are 

 divided transversely by whitish lines, the sides of the head checkered 

 likewise. The under parts are greenish white. 



The predominance of the fourteen rows of scales in the lineated 

 Western glass snake, in distinction from the sixteen of the mere check- 

 ered eastern form, appears to be well marked, at least in large specimens. 

 This is the case with Cat. No. 3193, from St. Louis, and a small one from 

 Knoxville, Tennessee, differing only in having the clay-colored strij)e, 

 on each side the dorsal brown one, 2| instead of If scales wide. The 

 latter was associated with a large one of the Atlantic type, with six- 

 teen series of scales. 



I did not observe this species in southwestern Texas, but obtained 

 it from near Dallas. The specimens are of the Western variety, with 

 only fourteen rows of dorsal scuta, or the subspecies attenuatus of 

 Baird. A specimen from the same locality is similar in tlie characters 

 named, but is remarkable for the strong carination of its superior 

 Scales. The carina) are elevated on the ten median rows, so as to leave 

 sulci between them. On the posterior part of the body the keels extend 

 to the lateral rows, and on the tail even to the inferior surface. There 

 are only ten superior labial scuta, and no postparietals. The infracan- 

 thal row extends over the eye, giving three rows between the latter 

 and the frontal plate. I am not sure that these characters are con- 

 stant, so I note this form under the varietal name of sulcatus. It is 

 described from a half-grown animal. 



The osteology of this species has been described by Miiller,' Dumeril 

 and Bibron,^ Cope-' (scapular arch in i)art), Fiirbringer,^ and Shufeldt.^ 



Observations. — Muller' erroneously states that the sternum is want- 

 ing in this genus. The figure of the scapular arch given by Dumeril 



' Zeitschr. f. Phj'siologie, IV, p. 227. ■• Knochen imd Muskeln, pp. 14, 43, pis. i, 



'^Erp. Gon. Atlas, YII, ligs. 5-9. fig. 8; in, fig. 36. 



sProc. Acad. Nat. Sci. Phila., 1864, p. L'28. f- Proc. U. S. Nat. Mus., IV, 1882, p. 397. 



