36 Annals of the Carnegie Museum. 



e. Pectorals normal ; teeth broad-tipped, 5-pointed, the points equal or 

 sub-equal. Pcecilobrycon, l3 Eigenmann 4 



ee. Pectorals fleshy flaps, edged with filaments ; teeth 3- or 5-pointed, the 

 middle point much the longest. Archicheir, Eigenmann 5. 



Genus Characidium Reinhardt. 



The species of Characidium of British Guiana fall into two groups. 

 (1) Rock-inhabiting Etheostoma-\\ke species, highly colored, moun- 

 taineers, with the outer pectoral rays thickened. (2) Pellucid species, 

 found on the sand-banks and resembling Ammocrypta in general 



appearance. 



Characidium laterale sp. no v. 



Type, 37 mm. (No. 1141 Carnegie Museum Catalog of Fishes.) 

 Amatuk. 



Cotypes, 3 specimens, 29-35 mm. Amatuk. (I. U. Cat. No. 

 11673.) 



A Zygonectes -like Characidium. 



Head 3.75-4; depth 6; D. 11 or 12; A. 8 ; scales 4-36-2. 



Eye equal to snout, 3.75 in head. Teeth three-pointed. Pectorals 

 reaching ventrals, its outer rays thickened ; ventrals three-fourths to 

 anal ; fourth anal ray reaching considerably beyond tip of last, but not 

 to the caudal fulcra. Base of dorsal reaching half way to middle of 

 adipose, about 7 in the length. 



A broad band from tip of snout to base of middle caudal rays, bor- 

 dered by a light streak above ; back brown, with darker cross shades; 

 a small spot just above base of first ventral ray ; a dark spot or streak 

 on the chin, another anterior to the anal ; a dark spot on either side 

 of base of anal, ventral surface otherwise plain. A dark spot anterior 

 to the dorsal and one in front of the adipose fin. Fins without definite 



markings. 



Characidium vintoni 14 sp. nov. 



(Native name, Tunatruic.') 



Type, 76 mm. (No. 1142 Carnegie Museum Catalog of Fishes.) 

 Shrimp Creek. 



Cotypes, 52 specimens, 53-82 mm. Shrimp Creek. (C. M. Cat. 



No. 1 143, a-j ; I. U. Cat. No. 11674.) 



13 The genus Poccilobrycon consists of the species described in this paper and 

 Nannostomus trifasciatus Steindachner, Nannostomus eqties Steindachner, and Nan- 

 nostomus tinifasciatus Steindachner. 



14 For Mrs. C. Vinton, one of the few ladies who have visited the habitat of this 

 species. 



