Classijication of the Order Ostariophysi. 17 



illarips, compressed, notched or denticu- 

 lated Brifcoiicethiops*, A/estes*, 



Fetersius*, Brycon, Chalcimis, Hennchihis, Bn/conops, 

 CreagrutKs, Deutrrodon, Pseudochalceus, Crenuc/tus'f, 

 Scissor, Bramocharar, Tetragonopteriis, Astijannx, 1 

 Sfichano(lon'\, Igunnodectes, Hemibrycon, Paragoniates, 

 Ggmnocharacinus, Diapoma, Corynopainrt, Pseudo- \ 

 corynopoma, Stethapn'oii, Brachychakinus. 

 Teeth in 2 series in the prfemaxillaries, the 

 outer or both conical or subcontcal ; anal 



of moderate length . , Siilmmns, Hystricodon, 



Agoniates. 

 Teeth unisorial, compressed, serrated in- 



cisois ; mouth small Chirodoti, Odontostilbe, 



Piabuca. 

 Teeth uniserial, compressed, pointed, notched 



or denticulated ; mouth larger Aphiocham.r, Mimagoni- 



ates, Leptayoniate^. 

 Teeth uniserial, conical, without canines ; anal 



not very elono;ate , Pho.vlnopsis, Ctenocharax. 



Teeth conical, with canines ; anal tin very 



long Charnx, Boeboides, Cyno- 



potamus. 



B. Abdomen keeled and serrated, bearing a median series of sharp- 

 edged bony plates with backwardly directed points : American. 



{Serrasalmonince.) Mylesinus, Pygocentvus, ~^ 



Pygopristis, Serrasalmo, Myletes. 



II. Prfemaxillaries movable ; maxillaries firmly united by suture with 

 the praemaxillaries : African. {ilydrocyon'mcB.) 



Hydrocyon. 



Tlie Cliaracinae correspond to about fourteen of Eigen- 

 mann's subfamilies; many of these are certainly natural 

 groups, inasmuch as they include but a single genus or two 

 or three closely related genera. Iguanochctes, Gijmno- 

 characinus, Diapoma, Corynopoma, Stichanodon, and Steth- 

 oprion are apparently quite as near to Tetragonopteriis and 

 Asti/nnax as the latter are to Brycon, and, in my opinion, 

 nothing is gained by making them the types of separate 

 subfamilies. 



Cbalcens and Plethodectes are placed by Eigenmann in the 

 Piabucininje, which he distinguishes from the Tetragono- 

 pterina3 by the absence of fontanels,, a character of very slight 

 importance. In the Characif'ormes the presence of fontanels 

 is probably sometimes a primitive feature, sometimes not ; 

 they have often become reduced or have disappeared or have 

 not developed, especially in those forms with the upper 

 surface of the head flatfish and the occipital crest low. 



* These genera are African, the other Characinae American. 

 t Teeth uniserial, but these genera are apparently related to the genera 

 with biserial teeth, after which they are placed. 



Ann. & Mag. N. Hist. Ser. 8. Vol. viii. 2 



