182 



MEMOIRS OF THE CARNEGIE MUSEUM 



Specimen No. 2038 was taken in the Rio Guapore, and according to Haseman's 

 note is called locally "Cobra de Agua." It presents some variations from the 

 description given by Boulengcr. The rostral is separated from the internasal by 

 the nasal. The frontal is once and two-thirds as long as broad, as wide in front 

 as behind, with perfectly straight and parallel sides. It is shorter than its distance 

 from the end of the snout, and shorter than the parietals. The anterior chin- 

 shields are longer and considerably larger than the posterior. There are no keels 

 on the scales of the outer row except in the posterior fourth of the trunk, and on 

 the tail. The color of the lower surface is dark brown, with only a few widely 

 separated small yellow spots. This appears to be the largest specimen of the 

 species which has been recorded. 



Specimens 319, 328, and 360 agree more nearly, but not entirely, with Bou- 

 lenger's description. The eye of all is longer than one-half the frontal shield; this 

 character is either more variable than usual or depends to some extent upon the 

 treatment of the specimen. The lower surfaces of Nos. 319 and 360 are almost 

 black, with round white (originally yellow?) spots on one or both extremities of 

 most of the gastrosteges, forming conspicuous rows. The lower surface of No. 328 

 presents only a few small and indistinct light spots. The dorsal surface of this 

 specimen is darker than that of any of the others, with more distinct black markings. 

 The three middle rows of dorsal spots tend in all the specimens to run into each 

 other and produce a pattern of diagonal crossing lines. 



Hypapophyses are not present at all on the posterior trunk vertebrae of two 

 of these specimens, and are scarcely indicated in the others. 



No. 319 was found under a barrel on the bank of the Amazon. No. 360 was 

 caught in a fish net in the Amazon. A small fish was found in the stomach of 

 No. 328. 



Counts and Measueements. 



(No. 319.) 



(No. 328.: 



(No. 360.) 



(No. 2038.) 



Anal 



Scale-rows 



Gastrosteges 



Urosteges 



Upper labials 



Preoculars 



Postoculars 



Temporals 



Total length in mm. . . . 

 Length of tail in mm. . . 



* Tip of tail lost, 



1/1 



23 



131 



71/71 

 8(4) 



1 



2 



1,2 



309 

 83 



1/1 



25 



119 



70/70 

 8(4) 



1 



2 

 1,2 



344 

 96 



1/1 



23 



130 



79/79 



8(3.4) 



8(4) 



1 



2 



Jl,2 



12,4 



407 



116 



1/1 



25 



122 



28/28* 



8(4) 



1 



2 

 2,3 



940 

 127* 



