THE AMERICAN TETRAGONOPTERINAE. 159 
rays tipped with dusky black, distal third of second anal rays white. Anal, 
ventrals, and pectorals yellow in life. Scales of the back outlined with pig- 
ment, a few large chromatophores scattered over the cheeks. 
16. HeMIGRAMMUS BOULENGERI Higenmann. 
Plate 78, fig. 3. 
Tetragonopterus fasciatus interruplus K1GENMANN (in part, non Liitken) Ann. N. Y. acad. sci., 1894, 7, 
p. 634 (Rio Grande do Sul). 
Hemigrammus boulengeri EIGENMANN & OGLE, Proc. U. 8. N. M., 1907, 33; p. 15; Eraenmann, Rept. 
Princeton univ. exped. Patagonia, 1910, 3, p. 436. 
Hasrrat.— Rio Grande do Sul. 
One specimen 11073 I. Type 45 mm. Rio Grande do Sul Von Ihering 
Head 3.33; depth 2.66; D.11; A. about 22, scales 5-30-3; eye 2.6 and 
interorbital 2.75 in the head. 
Compressed; depth of head at the base of the occipital process 3 in the 
greatest depth. Preventral region rounded, without complete series of median 
scales. Predorsal region rounded, with regular series of 11 scales. 
Occipital process 7 in the distance between its base and the dorsal, bordered 
by 3.25 scales. Interorbital slightly convex. Frontal fontanel triangular, 
broader than, and two thirds as long as, the parietal without the occipital 
groove. Second suborbital in contact with the preopercle. Snout short; 
mouth large. Maxillary 2.75 and mandible 2.33 in the head. Premaxillary 
with five 5-pointed teeth in the inner series, and three tricuspid teeth in the 
outer series. Maxillary with one 3-pointed tooth. Dentary with a graduated 
series of five 5-pointed teeth and three very small, 3-pointed teeth. 
Gill-rakers 6 + 8. 
Caudal probably scaled. Lateral line with pores on about 7 scales. 
Origin of dorsal half the length of the head nearer to the caudal than to 
the snout, penultimate ray 2.75 in the longest, which is almost 4 in the length. 
Origin of anal on the vertical from the first or second dorsal ray. Anal some- 
what emarginate, longest ray 1.25 in the base. Ventrals on the vertical from 
a point 1.75 the length of the eye in front of the dorsal. Ventral reaching to 
the base of the fourth anal ray. Pectorals a little more than reaching the 
ventrals. 
Humeral spot vertically elongate, distinct; a narrow black lateral line 
lying deeper than the caudal spot and not connected with it; caudal spot well 
