238 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 95 
are forced to ‘‘content ourselves with a combination of characters” 
summarized below: 
Mouth usually bordered by premaxillaries in the middle and 
maxillaries on the sides; teeth usually present on the jaws, only 
rarely on the palatine bones; soft rayed dorsal fin, usually followed by 
an adipose fin; body covered with scales; head naked; branchiostegal 
rays 3 to 5; gill arches 4; pseudobranchia lacking or rudimentary and 
glandular; coracoid sometimes forming a ventral ridge; pelvic rays 
usually number 10 to 13; the first ray of pectoral, dorsal, and anal rays 
but rarely ossified and never forming a sharp spine as in the Nematog- 
nathi; air bladder always divided into two parts by a constriction, 
anterior part smallest; usually about 10 to 40 caeca on stomach; 
intestines short or very long in herbivorous forms. 
TING Ea KEY TO THE GENERA AND TO CERTAIN SUBFAMILIES OF CHARACIN- 
IDAE REPORTED FROM VENEZUELA 
la. No teeth in either jaw and none on lips; nares close together, separated by 
a dermal flap; lateral line complete, straight, along midaxis of body; intes- 
tine greatly coiled, very long; caudal fin forked; adipose fin present. 
2a. Caudal lobes densely scaled to near tips; preventral area flat with a median 
series of scales and blunt lateral keels; postpelvic area with a median 
keel and two lateral keels converging toward anal, less developed in 
OULD Oe Gas ae Curimatella Higenmann and EHigenmann (p. 248) 
2b. Caudal fin scaled only a short distance out from base; gill membranes 
joined with each other and with a narrow free fold moderately forward 
on isthmus; lower jaw oblique, with hard edge; interorbital convex. 
3a. Roof of mouth with folds of tissue and sometimes with papillae; pre- 
dorsal plate absent; gill rakers short, numerous; low midventral ridge 
present from pelvics to anus but not well developed; scales large. 
Curimata Walbaum (p. 249) 
3b. Roof of mouth normal, without dermal folds or papillae; predorsal plate 
minute, bilobed; no scales in midline except middle third of length in 
young; gill rakers absent anteriorly, represented by a dermal fold; 
scales small; midventral ridge from anus to pelvics well developed. 
Anodus Agassiz (p. 251) 
1b. Teeth present in one or both jaws or on the lips. 
4a. Abdomen keeled, with a median series of sharp-edged bony plates with 
backward-directed points; body much compressed; anal base oblique, 
long; dorsal base long; scales small; a naked predorsal line; teeth strong, 
in one or two series in both jaws, usually with sharp cutting edges 
(Serrasalminae). 
5a. Teeth in a single series in both jaws; teeth with a strong median cusp and 
with either a single lateral cusp or a pair, those of upper jaw mostly 
ASVMMMEHrICAL UL RO HNN eee a Nae Serrasalmus Lacepéde (p. 254) 
5b. Premaxillary teeth in two series; mandibulary teeth in a single series; 
sometimes a pair of conical teeth behind and in contact with symphyseal 
mandibulary teeth; abdomen serrated before and behind pelvies; teeth 
more or less close-set, either incisorlike or with an oblique cutting edge 
or molariform; each premaxillary with 5 teeth in the outer and 2 in the 
inner series; jaws equal or lower jaw a little projecting; conical mandi- 
bulary teeth present. 
