THE AMERICAN TETRAGONOPTERINAE. 213 



Head 3.2-3.75; depth 2.9-4; D. 11; A. 22-26; scales 5-31 to 33-3 or 3.5. 

 Lateral line with pores on 5 to 10 scales. (One specimen had pores on 15 scales). 

 Eye 2.5 in head; interorbital three in the head. 



Compressed. Depth of head at the base of the occipital process 1.5 in the 

 greatest depth. Preventral region rounded, without complete median series 

 of scales. Predorsal region rounded, with a complete series of median scales. 



Occiptal process 4 in the distance from its base to the dorsal, bordered by 

 3.5 scales. Interorbital slightly convex. Frontal fontanel triangular, two 

 thirds of the parietal without the occipital groove. Second suborbital leaving 

 a narrow naked margin below and behind. Mouth large. Maxillary 3.5 in 

 the head, three fourths of the eye. Mandible longer than the eye, 2.4 in the 

 head. Premaxillary with an inner row of five 3- to 5-pointed teeth and an 

 outer row of two to five conical to narrowly tricuspid teeth. Maxillary with 

 two, rarely one, conical or 3-pointed tooth. Dentary with a series of four 

 graduated, 3- to 4-pointed teeth, followed by from four to nine minute conical 

 ones. 



Gill-rakers 13 +6, the last four on the horizontal limb very small. 



Anal sheath short, consisting of four or five scales. Lateral line with 

 pores on 5 to 10 scales, rarely on as many as 15. 



Origin of the dorsal equidistant from the snout and the caudal, penultimate 

 ray one third of the longest ray, which is 3 to 3.25 in the length. Origin of the 

 anal on the vertical from the second scale in front of the dorsal. Ventrals just 

 reaching the anal. Pectorals just reaching the ventrals. 



Humeral spot intense brown on a light circle or oval, covering the fourth 

 and fifth scales of the series just above the lateral line. A slim lateral stripe 

 of brown overlaid with a wider indistinct silvery stripe. No caudal spot. Sides 

 over the body-cavity somewhat iridescent. Fins hyaUne or uniformly a little 

 dusky. Specimens from Villa Bella have the scales of dorsal aspect outlined 

 with pigment and a few chromatophores scattered along the lateral stripe. 



Aside from having the dorsal scales outlined with pigment the specimens 

 from Villa Bella differed from those from Brazil (Hiatt Coll.) in being much 

 deeper. The original description of Steindachner gives 3.4 to 3.33 as the depth 

 of bellottii, the present specimens from Villa Bella are 2.4 to 3.33, those from 

 Brazil 3.67-3.9. 



