EEPTILES, • 213 



is preserved. The irpper surface and sides of heads are olivaceous brown, and the body and 

 tail above purplish grey. Beneath and anteriorly the hue is of a soiled white, whilst pos- 

 teriorly it is greyish yellow. The upper labials have the same hue as the lower surface of 

 head. A black line may be traced along the upper margin of the upper labials, from the snout 

 to about an inch and a half along the sides of the neck. Along the back and sides of the ante- 

 rior part of the body there are oblique series of jet black elongated spots. The lower and inner 

 margin of the scales is whitish, and apparent only when the skin is extended and the whole 

 surface of the scales exposed. The posterior portion of the body is sparsely dotted with black ; 

 the tail is unicolor. 



This species figured was collected on the island of Taboga, bay of Panama. 

 Plate XXXVI, fig. 1, represents DryopMs vittatus, of the size of life. 



fig. 2, view of the head, seen from above. 



fig. 3, side view of the head. 



fig. 4, under view of the head. 



fig. 5, vent and post-abdominal scutella. 



fig. 6, a portion of the left side of the body, showing the form and number 

 of longitudinal rows of scales. 



FAMILY OF COLUBRID^. 



Genus TACHYMENIS, Wiegm. 



Gen. char. Body subcylindrical, of moderate length ; tail short, subconical, tapering. 

 Head colubrine slightly detached from the body. Cephalic plates normal. Eyes of medium 

 size. One or two anteorbitals and two postorbitals. One loral. Two nasals, with nostril be- 

 tween them. Jaws subequal. Dorsal scales smooth. Preanal scutella bifid. Subcaudal 

 scutellte all divided. 



Syn. Tachymenis, Wiegm. in Nov. Act. Phys. Med. Acad. Nat. Cur. XVII. i. 1835, 251. 



Obs. The genus Tachymenis is, so far, composed of two species, one from Peru figured and 

 described by Wiegmann in the work cited above, and another from Chile, described below. 



TACHYMENIS CHILENSIS, Girard. 

 Plate XXXVII, Figs. 1—6. 

 Spec. char. Two anteorbitals. Third and fourth labials constituting the inferior rim of the 

 orbit. Dorsal scales in nineteen rows. Olivaceous brown above, with crossing lines of black. 

 Beneath yellowish, with anterior margin of scutellee black. Two postocular black vittse. 



Syn. Coronella chilensis, Schl. Ess. Phys. Serp. Part, descr. 1800,' 30. 



GuiCH. in Gay, Hist, de Chile, Zool. II, 1848, 79. Erpet. Plate iv, fig. 1, a, b, c, d. 

 Dipsas chilensis, DuM. Mem. Acad, des Sc. XXIII, 1853, 112. 



DuM. & B. Erp. gen. VII. i, 1854, 608. 

 Tachymenis chilensis,- Grd. Proc. Acad. Nat. Sc. Philad. VII, 1854, 226. 



Gen. rem. Of the three specimens that were collected, the one which is figured is the largest, 

 and yet hot fully grown. Though immature, we propose to describe them carefully, since the 

 figure in the Historia de Chile is not as accurate as might be desired. We have seen upon 

 specimens of others species, the zoological characters entirely developed when they bore the 

 same relations towards their adult as those now before us. 



