ON THE BATRACHIA AND REPTILIA OF COSTA RICA. 135 



This fine species is of aberrant character ; it resembles in size and coloration 

 the Thrasops prcestans, Cope, of the same region. 



85. Drymobius margaritiferus, Scblegel. 

 San Jose\ 



86. DRYMOBirs boddaertii, Seetz. 

 Talamanca and San Jose. 



87. Herpetodryas carinatus, L. 



Scales in ten longitudinal rows on the front, and eight on the posterior part of 

 the body, keeled and about as large as the parietal scuta excepting the first row 

 on each side, which is smaller and smooth. The keels of the two median rows 

 are stronger, and become very prominent on the posterior part of the body, forming 

 together an elevated flat-topped ridge, which gradually disappears on the tail, so 

 that the scales of its distal half are smooth. The third row of scales is smooth on 

 the posterior part of the body. There is usually a single pore at the end of the 

 scale, but sometimes it is wanting. Nine upper labial scuta, the fourth, fifth, and 

 sixth bounding the orbit. Loreal nearly as high as long ; oculars 1-2, the poste- 

 riors equal, the anterior not reaching the frontal. Last upper labials not elevated; 

 temporals 2-2. Parietals wide, short, as long as superciliaries, bounding a deep 

 notch behind. Gastrosteges 162; anal divided; urosteges 135. 



Color black above, below yellow, the former encroaching on the latter and 

 obliterating it on the posterior part of the belly, and on the tail. 



M. 



Total length 1.970 



Length of tail .......... .780 



" of head to rictus oris ....... .042 



The only specimen of this snake was taken from the stomach of an Oxyrrhopus 

 plumbeus of one foot less length. The tail and a portion of the body projected 

 from the mouth of its captor. From the low country. 



88. Herpetodryas grandisquamis, Peters; Spilotes grandisquamis, Peters, Mouatsberichte K. 



Akad. Berlin, 1868, p. 451. 



89. Spilotes pullatus, Linn.; Coluber variabilis, Wied. ; Spilotes variabilis, Dum. Bibr. 



90. Spilotes corais, Cuv., Giintber, Catal. Colub. Snakes Brit. Mus. 1858, p. 98; subspecies 



melantjrus, Dum. Bibr. 



This form ranges from Panama to northern Mexico, preserving the oblique 

 black mark on the neck and the black tail. When the black involves the entire 

 body and head, it becomes the subspecies S. c. erebennus {Spilotes erebennus, Cope; 



