206 THE AMERICAN CHARACIDAE. 
Anal sheath consisting of 11 or 12 scales graduated in size from the first and 
covering the bases of 11 to 13 anal rays. Lateral line with pores on 8 to 25 scales, 
the average being about 16 or less. Sometimes many of the scales immediately 
following those with the pores have a notch on the margin. 
Origin of dorsal equidistant from the snout and the base of the caudal 
or a little farther back, longest ray about 4 in the length. Caudal a little longer 
than the head. Origin of anal on the vertical from the fourth to ninth dorsal 
rays. Anal deeply emarginate, its longest ray 1.5 in the anal base. An anal 
armature developed on the first five rays of males 38-45 mm. long. Ventrals 
on the vertical from the third to fifth scales in front of the dorsal. Ventrals 
just reaching the anal. Pectorals a little more than reaching the ventrals. 
Dorsal hyaline, caudal spot forming a band on the end of the caudal 
peduncle, fainter above and below, rather abruptly continued posteriorly to 
the end of the middle caudal rays, gradually narrowed in front and continued 
forward in a dark lateral stripe; caudal lobes hyaline; humeral spot vertically 
elongate. Distal third of the anal dusky, basal two thirds of anterior rays free 
from pigment. Seales along the dorsal margined with dusky. A silvery 
iridescence on the sides except the upper two rows of scales. In life the caudal 
lobes, the anal and region just above the anal, and the dorsal probably are a 
shade of red or yellow. 
The five specimens from Sapucay (3015 em.) vary from typical specimens 
in having 25 to 29 anal rays. One of these specimens has also a 5-pointed tooth 
in the maxillary. 
26. HypHESSOBRYCON LUTKENI (Boulenger). 
Plate 28, fig. 2; Plate 79, fig. 1, 5. 
Tetragonoplerus fasciatus interruptus EXIGENMANN (in part, non Liitken), Ann. N. Y. acad. sci., 1894, 7, 
p. 634 (Rio Grande do Sul). 
Hemigrammus interruptus Fowuer (non Liitken), Proc. Acad. nat. sci. Phil., 1906, p. 335 (Jacuhy). 
Tetragonoplterus litkeni BouLENGER, Ann. mag. nat. hist., 1887, ser. 5, 19, p. 173 (Rio Grande do Sul); 
E1GENMANN & EIGENMANN, Proc. U.S. N. M., 1891, 14, p. 53; Unrey, Ann. N. Y. acad. sci., 1895, 
8, p. 287. 
Hemigrammus liitkeni Corr, Proc. Amer. philos. soc., 1894, 33, p. 91 (Rio Grande do Sul); Eraenmann & 
Kpnnepy (in part), Proc. Acad. nat. sci. Phil., 1903, p. 519 (Arroyo Pypucu; Arroyo Trementina) ; 
ErgenmMann, Ann, Carnegie mus., 1907, 4, p. 126, (Puerto Max, Colonia Gonzales). 
Hyphessobrycon liitkeni ErGeNMANN, Rept. Princeton univ. exped. Patagonia 1910, 8, p. 437; Exuis, 
Ann. Carnegie mus., 1911, 8, p. 159. 
Hasrrat.— Rio Grande do Sul and Paraguay Basins. 
