EIGENMANN: the freshwater fishes of BRITISH GUIANA 441 



283. Porotergus gymnotus sp. nov. 



Type, 70 mm. Amatuk. (Carnegie Museum Catalog of Fishes No. 1759.) 

 Cotypes, two specimens, 68-85 mm. Amatuk. (I. U. Cat. No. 12636.) 

 Cotype, one specimen, 62 mm. Konawaruk. (C. M. Cat. No. 1758a.) 

 Head 6-6.5, greatest depth 6.2-6.7 in the length to the end of the anal. A. 130- 

 147; snout 2.2-2.5, interorbital about the same in the head; eye 5-6 in the snout 

 and 12-14 in the head; five to eight rows of scales above the lateral hne; a mid- 

 dorsal stripe, naked and abundantly supplied with mucous pores. 



Compressed and slender; depth of the head in occipital region 1.25-1.5 in 

 the greatest depth ; anus not quite the length of the snout behind the vertical from 

 the eye; dorsal profile behind the head almost straight, the head sharply sloping; 

 ventral profile slightly convex, save in the mental region, where it is rather concave. 

 Snout heavy and somewhat truncate; mouth moderately large; gape straight, 

 not quite or just barely reaching below the eye; jaws stout, lower included on the 

 sides; teeth few, small, conical, in two irregular interrupted rows, the inner one 

 of the lower jaw represented by but three or four teeth; two small patches of not 

 over six teeth each in the upper jaw. 



Caudal 2.8 in the head, pectorals 1.3; origin of the anal a little in front of the 

 gill-opening. 



Ground-color dark golden brown, darker dorsally; scales outlined with dark 

 bro\vn; upper parts of the head and back, as well as a spot at the origin of the 

 lateral line, almost black; cheeks brown with numerous minute yellowish dots; 

 lips, the openings of the mucous canals in the mid-dorsal region, the anus, and a 

 small spot at origin of caudal, yellowish; fins hyaline. 



284. Porotergus gimbeli sp. nov. " 



Type, 205 mm. Para, January 22, 1910 (Haseman). (Carnegie Museum 

 Catalog of Fishes No. 3197.) 



Cotypes, two specimens, 170-140 mm. Para, January 22, 1910 (Haseman). 

 (C. M. Cat. No. 31980.) 



Cotype, one specimen. Hubabu Creek, British Guiana, October 1, 1910 

 (Ellis). 



Head 8.5-10.25; greatest depth of the body 8.25-9 in the length to the base of 

 the caudal; A., type, 175, cotypes, 178, 167, 180. 



Snout 3-3.6, interorbital 4-5 in the head; eye 3-3.5 in the snout, 2-2.8 in 

 the interorbital, and 11-14 in the head; lateral line prominent, extending out on 



" Named for Mr. J. Gimbel, whose generosity made the Gimbel Expedition possible. 



