Jordan and Evermami. — Fishes of North America. 331 



line on one side to that on tlie other; sides mottled with light or dark 

 brown. Panama to Ecuador, chiefly west of the Andes. Known from 

 Rio Chagres and from Ecuador. (Eigenmann). {tnKpbg, small; /.e-Kiq, 

 scale.) 



Maerndaii mii-rolepix, GvNTHEn, Cat., v, 2S2, 1864, Western Ecuador ; Chagres River, 

 Guatemala ; (Coll. Fraser.) Eicexmann, Ann. N. Y. Ac. Sci , 1889, 102. 



Family XXXIX. CHARACINID.^. 



(Thk Characins.) 



Heterognaths with the skull above more or less invaded by reentering 

 valleys from behind, and the supra-occipital partly superior and carinated 

 by a procurrent crest. (Gill). Body variously formed, covered with 

 cycloid scales. Head naked. Margin of upper jaw formed mesially by 

 the premaxillaries and laterally by the maxillaries ; no barbels ; premax- 

 illaries not protractile. Teeth various, often incisor-like, often wanting. 

 Branchiostegals usually 3. Gill membranes united to the isthmus or not ; 

 no pseudobranchiip; gills 4, a slit behind the fourth ; lower pharj-ngeals 

 not truly falciform, but more or less curved, armed with small, sometimes 

 villiform teeth. Adipose fin present or absent.* Pyloric cceca usually 

 numerous. Air bladder transversely divided into two portions, and com- 

 municating Avith the organ of hearing by means of auditory ossicles, as 

 in Cinn-inidw; anterior vertebne coalesced and modified. A very large 

 family of some 55 genera and 300 species, inhabiting the fresh waters of 

 South America and Africa, where they take the place of the Salmonidce 

 and Ciiprinidw of the Northern Hemisphere. A single species reaches the 

 United States. The few species enumerated below are but the overflow 

 of the vast South American river fauna. 



(CharacMdis, Gunther, Cat., v, 278-380, 1864). 



Curimatin.t; : 

 a. Dentition imperfect. 



b. Teeth none ; no gill rakers ; belly trenchant or not, with a median series of scales not 



ending in spiniform processes ; lateral line complete ; mouth nearly horizontal ; 

 tongue adnate, short and thick. Curimata, 138. 



aa. Teeth well developed in hoth jaws ; dorsal fins short ; gill openings wide, the membranes 

 not attached to the isthmus ; nostrils close together. 

 Tetragonopterin.t-: : 



c. Teeth compressed, notched or denticulated. 



d. Anal fin short, (10 to 12 rays) ; no lateral line ; premaxillary teeth in one eorios. 



PiAiiUriNA, 139. 

 dd. Anal fin more or less elongate ; lateral line more or less developed, 

 e. IJelly in front of ventrals rounded ; gill rakers slender. 



/. Premaxillary teeth in a double series ; no conical teeth behind front teeth 



of lower jaw. Tetragonopteris, 140. 



ff. Premaxillary teeth in three or four series ; a pair of conical teeth behind 



middle of the front series of teeth in lower jaw. Brtcon, 141. 



ee. Belly in front of ventrals compressed ; no canines ; ventral fins very small. 



Gasteropelecus, 142. 



♦Theadipope fin in Characinidit \s probably a survival from a remote ancestry which they 

 share with Siluroid forms. In the Salmnnidn, it is doubtless also a survival, but notwithstanding 

 the superficial resemblances in certain genera, (aS Cin-inintbuv and t '(iregnniiiir,) thoro ia no evi- 

 dence of any special relationship between the Sidmunid.e and Chnraciuidic . They should not be 

 placed in the same order ; scarcely even in related orders. The adipose fin in Pcrcojisidie is 

 probaby also an independent survival. 



