316 FISHES OF WESTERN SOUTH AMERICA 
439. EIGENMANNIA TROSCHELI (Kaup) 
Sternopygus troscheli Kaup, 1856, Cat. Apod., 139; 
Steindachner, 1868, Sitzb. KIk. Akad. Wiss. Wien, LVIIT, 12; 
Giinther, 1870, Cat. Fish. Brit. Mus., VIII, 8. 
Sternopygus troschelu. Cope, 1878, Proc. Amer. Phil. Soc., X VII, 682, Peruvian Amazon. 
Eigenmannia troscheli Eigenmann and Ward, 1905, Proce. Wash. Acad. Sci., VII, 174; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 449; 
Ellis, 1913, Mem. Carnegie Mus., VI, 131, pl. xxii, fig. 2; 
Fowler, 1915, Copeia, no. 15, Peruvian Amazon; 
Fowler, 1939 (1940), Proc. Acad. Nat. Sci. Phila., XCI, 276, one, 185 mm., Contamana. 
Upper Amazonia of Peru and Brazil 
15995, 3, 255-275 mm., Iquitos, Morris, 1922. 
15609, 11, 234-275 mm., Iquitos, Allen, September, 1920. 
15422, 4, 105-210 mm., Lago Cashiboya, Allen, August, 1920. 
440. EIGENMANNIA CONTIROSTRIS Eigenmann and Allen, sp. nov. 
Plate XVI, figs. 2 and 5 
15739, 5, type and paratypes, 270-346 mm., Iquitos, Allen, September and November, 1920. 
Head 12.0-12.25; depth 7.8-8.2 in the length; eye 9 or more in the head, 3.2 
in the snout, 2.6 in the interorbital width; maxillary 5; interorbital space 3.7; 
dorsal and ventral contours of the head nearly rectilinear, wide at occipital, and 
narrowing uniformly toward the snout; head slightly, and body greatly, compressed ; 
width of head at opercle in the 300-mm. specimen 12 mm.; depth at occipital 
18-19 mm., or two in the greatest depth of the body, or near 1.33 in the length of 
the head; snout conical, 3 in the head; mouth small, its width 1.33 in the inter- 
orbital space; jaws nearly equal, the lower fitting into the upper; eyes small. 
Anus nearer the vertical from the eye than to the end of the operculum; 
depth at the origin of the caudal filament 5 mm.; length to the end of the anal fin 
220 mm., the head to the eye 9.0—-9.5 mm.; eye 2.5 mm.; maxillary 5.0 mm.; inter- 
orbital 6.5 mm.; anus situated 20 mm. from the tip of the snout; anal fin 192-197 
mm., its origin beneath that of the pectoral; anal rays 242-259; pectoral equal to 
head without snout, 17 mm. long. (Measurements from type; counts taken also 
from paratypes. ) 
Scales cycloid and largely deciduous; back partly naked; caudal filament flat 
and ribbon-like, moderate length, 3.7 in the total length of the fish. 
Color in alcohol pale buff, little changed from life; very shghtly darker along 
the dorsal line; no markings along the lateral line; anal hyaline, fringed with 
dusky, resembling some of the specimens of FE. virescens. 
A paratype 346 mm. in length, head 28 mm., is a gravid female as of November. 
The species is near /. virescens and troscheli, but unlike in the shorter, conical 
head, small eye, short, compressed caudal filament and color. 
Genus 175: RHABDOLICHOPS Eigenmann and Allen, gen. nov. 
Five of our specimens resembling those of Eigenmannia closely in many re- 
spects, are different in the following characters: 
