52 THE AMERICAN CHARACIDAE. 



B. No adipose fin ; lateral line incomplete ; 

 outer and middle caudal rays of the 

 male filiform. 



20. Nematobrycon Eigenmann. 

 BB. Adipose fin present. 



C. Anal very short, with but ten rays. 

 21. Microgenys Eigenmann. 

 CC. Anal moderate or long. 



D. Outer row or premaxillary teeth 

 the dominant one. Gill-rakers 

 branched. 

 22. Ceralobranchia Eigenmann. 

 DD. Inner row of premaxillary teeth 

 at least as well developed as 

 the outer. Gill-rakers simple. 

 E. Few teeth along the upper por- 

 tion of the maxillary. 

 23. Bryconamericus Eigenmann. 

 (F. Males with a pouch covered 

 with scales at the base of 

 the caudal. 



Argopkura Eigenmann. 

 FF. Males without a pouch on 

 the caudal. 



Bryconamericus.) 

 EE. Teeth along the greater part or 

 along the entire edge of the 

 maxillary. 



24. Hemibrycon Gunther. 

 qq. Premaxillary teeth in three series. 



G. Anal short of not more 

 than 14 rays. 

 25. Crcagrutus Gunther. 

 GG. Anal of 20 or more rays. 



26. Piabina Reinhardt. 



ee. Maxillary border meeting premaxillary border at a right angle, its upper anterior margin 



then describing a quarter circle and continued in a direction nearly parallel with that of 



the premaxillary border; maxillary slender, partially slipping under the preorbital and 



first suborbital for nearly its entire length. Plate 2, fig. 5. 



H. Lateral line incomplete. 

 27. Brycochandus Eigenmann. 

 HH. Lateral line complete. 

 /. Premaxillary teeth 



five-pointed, in an 

 outer row of 6-10 

 teeth; anterior man- 

 dibular teeth strong- 

 er than those of the 

 premaxillary, 10-12 

 in number; sides of 



