18 Br. A. Giinther on new Species of Snakes 



scale-like posterior. Ventrals 180; subcaudals 71. Upper 

 parts greyish, with a white collar; a pair of brown bands 

 edged with black, and two scales broad, run along the back 

 from the collar to about the middle of the tail. A similar 

 band along each side of the body, and sometimes a narrow 

 blackish line along each edge of the abdomen. Lower parts 

 uniform white. Upper labials white, with a black spot below 

 the eye and on the rostral shield. 



This snake does not appear to be uncommon in the elevated 

 country of Costa Rica, near Cartago. 



Total length 12^ inches, tail 3 inches. 



Streptophorus Sehce (D. & B.). 



Having seen numerous examples of this snake collected at 

 Cartago in Costa Rica, I regard the Str. maculatus of Peters 

 (Berlin. Monatsber. 1861, p. 924), likewise from Costa Rica, 

 as a variety. Specimens with or without spots on the abdo- 

 men, with or without black on the head and neck, occur in the 

 same locality, the ornamental colours being subject to great 

 individual variation. 



Ahlahes gracilis. PL III. fig. D. 



Body and tail slender, subcylindrical ; head narrow, not 

 distinct from neck. A pair of narrow anterior frontals ; 

 posterior frontals confluent into one large shield. Rostral 

 rounded. Nostrils small, between two nasals. One loreal ; 

 one anteocular and one postocular. Eye small. Scales smooth, 

 with a single apical groove, in fifteen series. Anal and sub- 

 caudals double. The posterior maxillary teeth become gra- 

 dually larger, and are smooth. Rostral shield very broad and 

 low ; anterior frontals narrow, nearly the entire upper surface 

 of the snout being occupied by the single posterior frontal. 

 Vertical broad and long, five-sided, with the posterior angle 

 produced and pointed ; occipitals as long as the vertical and 

 posterior frontal together. Nasal shields small ; loreal longer 

 than deep ; preeocular narrow, not extending to the upper 

 surface of the snout. Seven upper labials, the third and 

 fourth entering the orbit. Temporals 1 + 1-1-2. The first 

 pair of lower labials form a suture together; two pairs of 

 chin-shields, subequal in size. Ventrals 149 ; subcaudals 69. 

 Upper parts nearly uniform blackish brown, the anterior and 

 lateral scales somewhat lighter in the centre. An indistinct 

 naiTow brownish collar. Lower parts yellowish. 



One specimen from the elevated country of Costa Rica, near 

 Cartago. Total length 12 inches, tail 3 inches. 



