SOUTH AMERICAN NEMATOGNATHI. 473 



interorbital. Snout compressed, pointed; preorbitals very 

 narrow, rictal barbels extending about to the gill-open- 

 ing, the outer one brown, the inner white; lower lip broad, 

 free, terminating in two barbels; upper surface of the 

 maxillary bones with fine bristles. 



Coracoid process scarcly encroaching on the breast or 

 belly. 



Two or three azygous plates in front of the adipose fin. 



Distance of the dorsal spine from the snout 2 in the 

 length; dorsal spine little if any shorter than the head, 

 its anterior margin smooth, its posterior margin finely 

 serrate; first two dorsal rays higher than the spine. 



Caudal deeply forked, 2| in the length. 



Pectoral spine similar to and little longer than the dor- 

 sal spine. 



Light brown, sides and back with blackish-brown spots; 

 a dark vertical bar below the eyes; occiput blackish; a 

 dark brown vertical bar on the first two dorsal rays, 

 sometimes continued on the sides, the remainder of the 

 fin plain or spotted with dark brown; caudal with 4-5 

 dark brown cross-bars; anal barred or spotted with 

 brown; other fins plain; opercle and humeral process 

 with silvery reflections. 



Head 3J; depth 2f-3; D. I, 8; A. 8; V. 6; P. I, 8-9; 

 Lat. pi. ||-|f 



Six specimens .045-. 05 m. Jose Fernandez. Maj. 

 Coutinho. 



464. Corydoras trilineatus. 



Cori/rforu* fnlineatus Cope, Proc. Acad. Nat. Sci. Phila. 1871, 281, 



pi. 6, fig. 2 (Ambyiacu). 

 Corydoras aijassizii Steindachiier, Ichthyol. Beitr. v, 90 aiid 186, 



pi. 12, figs. 2-2<x (Tabatiuga). 

 Habitat: Maranon and its tributaries. 



Dr. Cope's figure represents an individual .049 m. 

 long; it has the snout blunt and eye large. Dr. Steiii- 

 dachner figured an individual .07 m. long, which has a 

 longer snout and smaller eye, but on page 186, 1. c., Dr. 



