134 



ON THE BATRACHIA AND REPTILIA OF COSTA RICA. 



84. Dendrophidium melanotropis, Cope, sp. nov. 



The genus Dendrophidium was first defined by the writer in the Proceedings 

 Philada. Academy, 1860, p. 561. Its dentition is isodont and coryphodont, in 

 which, with its two preoculars, it resembles Bascaniwn (Masticophis). From this 

 genus its strongly keeled scales separate it. Its type is Herpetodryas dendrophis of 

 Schlegel: a second species is H. brunneus, Gthr., from Equador. 



Posterior maxillary tooth a little longer and much stouter than the anterior 

 teeth, the three or four preceding teeth forming a graded series of intermediate 

 size. Scales in seventeen series, all keeled excepting the inferior two on each 

 side ; the lateral scales wider than "the median ; the keels of the row on each side 

 of the vertebral stronger than those of the others. Gastrosteges not angulate- 

 Head elevated, eye large, its diameter one and a half times in the length of the 

 muzzle, and equal to the width of the frontal and one superciliary shield. Supe- 

 rior labials nine, the fourth, fifth, and sixth entering the orbit. These plates are 

 rather small to the eighth, which is much longer than high, and the ninth, which 

 is higher than long. Rostral plate not protuberant, wider than high ; postnasal 

 higher than prenasal. Loreal much longer than high, angulate above owing to 

 the oblique suture with the superior preocular, Preoculars two, the superior wide, 

 not reaching the frontal ; the inferior much smaller, resting on the middle of the 

 fourth superior labial; on one side united with the superior preocular. Postoculars 

 two, equal, narrow and elevated. Temporals 2-2, short and deep. Internasals 

 longer than wide ; prefontals longer than wide ; frontal bell-shaped, wide in front, 

 contracted behind; superciliaries rather narrow. Parietals wide, remarkably short, 

 their greatest length equal to that of the frontal, less than that of the superciliary ; 

 their posterior borders convex, including a notch. Scales behind them smooth. 

 The scales of the body are biporous, the pores situated at a distance in front of 

 the apex of the scale, and dark pigmented. Gastrosteges 152; anal divided; 



urosteges 94. 



Color above and including the external fourth of the gastrosteges green ; the 

 skin between the scales and the keels of the median three dorsal rows, black; 



lower surfaces light yellow. 



M. 



Total length 1-240 



Length of tail . 



" to rictus oris 

 Width between supercilia 

 Diameter of eye 



.365 

 .035 



.072 

 .008 



