78 Field Museum of Natural History — Zoology, Vol, X. 



Body elongate, the dorsal region elevated; profile slightly convex; 

 mouth sub-inferior, 5^ of band of premaxillar>'' teeth exposed; band of 

 teeth in lower jaw about >^ width of the premaxillary band; maxillary 

 barbels reaching end of shortest caudal rays; eye 4.15 in head; snout 

 2.30; interorbital 3.86; dorsal rather high, its spine 1.20 in head; first 

 dorsal ray 1.04; last dorsal ray 2.82; longest dorsal ray not reaching 

 adipose fin; depth at origin of adipose fin 2.04 in head; depth of caudal 

 pedimcle 5.50; base of adipose fin 1.41 in head; pectoral spine slightly 

 roughened on outer margin, its inner margin with 24 rather strong 

 retrorse teeth, its length 1.28 in head; humeral process scarcely reaching 

 middle of pectoral spine, its length 2.47 in head; caudal fin deeply 

 forked. 



Color light silver}' below, darker above; sides and top of head with 

 many small black spots. 



Tuyra River basin. 



riegalonema robustum sp. nov. 



Type No. 7578, F. M. N. H. ; length 290 mm. ; Rio Tuyra, Marriganti, 

 Panama. 



Head 3.8; depth 4.4; D. I, 6; A. 10. 



Body elongate, robust, profile nearly straight; dorsal region ele- 

 vated; mouth sub-inferior, about half of band of premaxillary teeth 

 exposed; band of teeth of lower jaw nearly as ^\'ide as premaxillan,' band; 

 maxillar}' barbels reaching to or sHghtly past middle of adipose fin; eye 

 5.0 to 5.6 in head; snout 2.3; interorbital 3.0 to 3.4; dorsal fin rather 

 high, its spine i.i to 1.2 in head; first dorsal ray .9 to i.i ; last dorsal ray 

 2.8; longest dorsal ray not reaching adipose fin; base of adipose fin 1.2 

 in head; depth at origin of adipose fin 1.5 in head; depth of caudal 

 pedimcle 3.1 to 3.2; pectoral spine roughened on outer margin, the 

 inner vi4th 32 rather small retrorse teeth, its length i.i in head; himieral 

 process 2.3 in head, not reaching middle of pectoral spine. 



Color dark olivaceous above, silvery below; sides and head without 

 spots. 



Tuyra River basin. 



Family PYGIDIID^. 



Pygidium striatum sp. nov. 



Type No. 7579, F. M. N. H.; length 84 mm.; Rio Cana, Cana, 

 Panama. 



Head 5.3 to 6.3; depth 7.4 to 8.2; D. 8; A. 6. 



