THE AMERICAN TETRAGONOPTERINAE. 161 
Origin of dorsal less than half the length of the eye nearer the caudal than 
the snout. Penultimate ray two fifths of the longest, which is 3.2 in the length. 
Origin of the anal on the vertical from the first to third scale behind the dorsal. 
Anal deeply emarginate, the longest ray almost equal to the base. Caudal a 
very little longer than the head. Ventrals on the vertical from the second or 
third scale in front of the dorsal. Ventrals just reaching the anal, pectorals 
barely reaching the ventrals, more often only reaching to the second or third 
scale in front of the ventrals. 
Humeral spot conspicuous, black, vertically elongate, surrounded by a 
small light area. Caudal spot variable in intensity, vertically elongate, I-shaped, 
not extending on to the caudal rays, and not continuous with the narrow black 
lateral stripe, which is overlaid with silvery. Scales of the postdorsal region 
each marked with a round dark spot in addition to a few scattered chromato- 
phores. Scales of the predorsal region with round spots less distinct and the 
general dusky shading more pronounced. Scales of the sides above the lateral 
stripe outlined with dusky. A few chromatophores scattered over the region 
between the anal and the lateral stripe. Some indications of a very faint 
secondary humeral spot. Fins all a little dusky. Caudal with an orange spot 
on the base of each lobe (evident in fresh specimens only). 
18. HEMIGRAMMUS BARRIGONAB Eigenmann and Henn. 
Plate 93, fig. 2. 
Hemigrammus barrigonae K1geNMANN & HENN, Indiana univ. studies, 1914, no. 24, p. 232 (Barrigona). 
Hasitat.— Rio Meta, Colombia. 
Specimens examined. 
Number of Size 
Catalogue number specimens in mm. Locality Collector 
13423 I. Type 1 41 Barrigona, Rio Meta Gonzales 
13424 I. Paratypes 65 25-43 Barrigona, Rio Meta Gonzales 
Head 4; depth 2.6-3; depth of caudal peduncle 9-10; D. 11; A. 24-25. 
Scales 33-35 in a longitudinal series, about 11 in a transverse series. Develop- 
ment of scales with lateral line pores extremely variable and not even equal 
on both sides of the same specimen. Usually a continuous series of at least 
14 seales with pores, thence lateral line discontinuous; pore usually developed 
on last scale in the series. One specimen has the lateral line 7/6 + 3 + 7 + 
