PISHES OF WEST COAST OF PEEU. 27 



Head 3.36 to 4.3 in trunk ; snout 4.32 to 5.1 in head ; eye 3 to 3.57 

 in snout, 15.3 to 15.8 in head; gape of mouth 2.03 to 2.55 in head; 

 branchial aperture greater than diameter of eye; nasal tube about 

 two-thirds eye in height ; tail equaling length of body ; snout blunt ; 

 eye situated above center of gape of mouth ; a row of well-developed, 

 recurved, subequal, compressed teeth on jaws, about 40 on upper 

 and 50 on lower; outside these there is a supplementary row (easily 

 overlooked) close to base and usually opposite interspaces be- 

 tween larger teeth, these best developed on front of jaw; 3 longer, 

 fanglike teeth on palatines, posterior to eye; 3 or 4 recurved 

 fanglike teeth on front of vomer, followed by an interspace, then 

 a row of 12 or more small subequal teeth; in our largest specimen 

 the anterior teeth in this roAV are somewhat irregiilarly placed, tend- 

 ing to form two rows. 



Color in alcohol, chocolate-brown, marbled with darker and 

 lighter; belly lighter, marblings not so distinct. Color-pattern diffi- 

 cult to describe because of its great irregularity. 



Color in life : Entire body and head, dirty brown, mottled. 



These specimens agree in all essential characters with the descrip- 

 tion by Sauvage. 



Family CHARACINIDAE. 



THE CHAEACINS. 



KEY TO C4EXERA REPRESENTED. 



a"'. Adipose fin present. 



&\ Maxillary completely toothed ; intermaxillary with three series of notched 

 or tricuspid teeth ; nostrils close together ; gill-membranes free from 



isthmus Brycon, p. 27. 



&l Maxillary not completely toothed Astyanax, p. 27. 



ol No adipose fin; maxillary without teeth LeMasma, p. 29. 



Genus BRYCON Miiller and Troschel. 



31. BRYCON ATRICAUDATUS (Kner). 



Chalceus atricaudatus Knee, Sitzgsber Akad. Wiss. Miinchen, 1863, p. 227. 



Brycon atricaudatiis GtJNTHEE, Cat. Fish. Brit. Mus., vol. 5, 1864, p. 336. — 

 Stakks, Fishes from Ecuador and Peru, Proc. U. S. Nat. Mus., vol. 30, 

 1906, p. 777; Paita and Eteu, Peru. — Eigenmann, Cat. Fresh-water 

 Fish. Trop. and South Temp. America, 1910, p. 431. 



Genus ASTYANAX Baird and Gerard. 



32. ASTYANAX PERUANUS (Muller and Troschel). 



ANCHO. 



Tetragonoj)terus penianus Mtjller and Troschel, Hor. Ichth., vol. 1, 1845, 

 p. 28, pi. 8, fig. 1 ; Peru. — Cuvier and Valenciennes, His. Nat. Poiss., 

 vol. 22, 1849, p. 115 (153). — Stares, Fishes from Ecuador and Peru, 

 Proc. U. S. Nat. Mus., vol. 30, 1906, p. 775. 



