148 THE AMERICAN CHARACIDAE. 
Hemigrammus nanus E1GENMANN & OGLE, Proc. U.S. N. M., 1907, 33, p. 15; Eraenmann, Rept. Prince- 
ton univ. exped. Patagonia, 1910, 3, p. 435. 
Hapitat.— San Francisco Basin. 
44958 U. S. N. M., 4 Cotypes Lagoa Santa Reinhardt 
Head 3.9; depth 3.5-4; D.11; A.17-19; scales 35-30 to 32-2.5 to 3; 
eye 2.2 in the head, interorbital narrower. 
Compressed; depth of head at the base of the occipital process 1.33 in the 
greatest depth. Preventral region rounded, without complete series of median 
scales. Predorsal region rounded with complete median series of 11 scales. 
Occipital process one seventh of the distance from its base to the dorsal, 
bordered by two and a half scales. Interorbital region somewhat convex. 
Second suborbital leaving a narrow naked area below and a much narrower 
one behind. Maxillary much shorter than the eye, 3.25 in the head. Mandible 
nearly as long as the eye, 2.75 in the head. Premaxillary with four, 3-pointed, 
teeth and sometimes one conical tooth in the inner row, and two similar but 
narrower teeth in the front row. Maxillary without teeth or with one tooth. 
Caudal probably scaled; anal sheath of probably a single series of scales 
extending the entire length of the base of the fin. Lateral line with pores on 
from 4 to 7 scales. 
Origin of the dorsal half length of the eye nearer the caudal than the snout, 
penultimate ray one third of the longest which is 4.2 in the length. Origin 
of the anal on the vertical from the last dorsal ray. Height of the anal nearly 
equal to the length of its base. Anal emarginate. Base of the ventrals on the 
vertical from the second or third scale in front of the dorsal. Ventrals not 
quite reaching the anal, and pectorals almost reaching the ventrals. 
Fins all hyaline except where the large, diffuse dark caudal spot extends 
over the caudal, often reaching the ends of the middle rays. No humeral spot. 
An inconspicuous, silvery lateral band. The scales of the back outlined with 
pigment, a few chromatophores scattered over the sides except above the body- 
cavity. 
8. HeMIGRAMMUS LEVIS Durbin. 
Plate 18, fig. 2. 
Hemigrammus levis DurBin, Bull. M. C. Z., 1908, 62, p. 100 (Lago do Maximo); Ercenmann, Rept. 
Princeton univ. exped. Patagonia, 1910, 3, p. 486; Exuis, Ann. Carnegie mus., 1911, 8, p. 162 
(Santarem). 
HapiratT.— Amazon. 
