48 



INDIANA UNIVERSITY 



maxillary border nearly lialf the leii.ijth of the head in the largest female, 

 shorter in the younger females and in the males. 



Heaviest at end of pectorals : preventral area broad, rounded, ^Yith 

 irregularly placed scales; post.Tentral area rounded, rather broad; predor- 

 sal area broad, completely sealed but \Yitliout a distinct median series of 

 scales ; about 13 series of scales in front of the dorsal. 



Occipital process G in the distance from its base to the dorsal ; interor- 

 bital smooth, convex ; second suborbital short and deep, its margin very 

 convex, leaving a narrow naked area of about equal width around its 

 entire margin in the females, in the males much less convex, the naked 

 area much wider. Outer series of premaxillary with three to five teeth, 

 inner row with fixe teeth, the tooth at the symphysis three-pointed, the rest 

 live-pointed incisors. Maxillary with one to seven teeth, the outermost 

 sometimes conical, the innermost three-pointed. Mandible with four large 

 teeth, two smaller ones and about eight minute ones, all about five-pointed, 

 the middle-point much the longer. Scales cycloid, with very many (often 

 twenty or more) diverging striae, regularly imbricate, except just over the 

 origin of the anal, the exposed edges of the scales of the sides about half 

 as wide as high ; caudal naked ; anal sheatli of a single series of incon- 

 spicuous scales confined to the first nine anal rays ; lateral line but little 

 decurved. the row of scales below it parallel with it. 



Origin of dorsal equidistant from ti]) of snout and last scale at base of 

 middle caudal rays, its penultimate ray half as high as the highest, which 

 is 0 in the length ; anal slightly emarginate, its origin behind the vertical 

 Ircni the last dorsal ray, its base just equal to the distance between the 

 dorsals or shorter. 4 in tlie distance from the pupil to the caudal in the 

 largest female, G in the length in the largest male ; ventrals a little, if 

 any. in advance of the origin of the dorsal, short and rounded, reaching to 

 the anus ; pectorals quite small, reaching half-way to the middle of ven- 

 trals in the largest female, a little further in the largest male. 



A vertical humeral bar just behind the opercle, a silvery lateral band 

 Ijecoming dark toward the caudal and continued, but much narrower on 

 the middle caudal rays the continuation on the caudal being sometimes 

 scarcely apparent 



23. Pygidium hasemani Eigenmann sp. nov. 

 5238 C. M. type, -5239 C. M. paratypes, many, largest 18 mm. Santarem. 

 Dec. 11 ,1909. Haseman, 



This species resembles Pygidium amazonuni (Steind.) in the posterior 

 position of the dorsal. The origin is on the vertical or a little posterior t(» 

 the vertical from the anal. 



Head 5.5 ; depth 7 ; D. 7 or 8 ; A. 6 or 7 ; caudal with 12 radiating 

 rays and numerous accessory rays, both above and below. Eyes about 5 in 

 the head, about 2 in the interorbital ; posterior margin of eye in advance 

 of middle of head ; poctoral prolonged in a filament ; maxillary barbel not 

 extending beyond the preopercular spines ; pectoral about equal to length 

 of head; ventrals hut little over half length of head. A series of about 8 

 diffuse dusky spots along the middle of the back in front of the dorsal ; 

 middle of sides with about 8 minute more intense spots, the last of which 

 is at the base of the middle caudal rays. 



