Series Ostariophysi 163 
yngeals, which are scythe-shaped and in typical forms are armed 
with a relatively small number of highly specialized teeth of 
peculiar shape and arranged in one, two, or three rows. In 
all the species the gill-openings are restricted to the sides; there is 
no adipose fin, and the broad, flat branchiostegals are but three 
in number. In all the species the scales, if present, are cycloid, 
and the ventral fins, of course, abdominal. The modification 
of the four anterior vertebra and their connection with the 
air bladder are essentially as seen in the catfishes. 
The name Plectospondyli is often used for this group (zAexrés, 
interwoven; owordvaos, vertebra), but that term originally in- 
cluded the Characins as well. 
The Cyprinide.—The chief family of the Eventognathi and the 
largest of all the families of fishes is that of Cyprinide, comprising 
Fic. 122.—Pharyngeal bones and teeth of European Chub, Leuciscus cephalus 
(Linneeus). (After Seelye.) 
200 genera and over 2000 species, found throughout the north tem- 
perate zone but not extending to the Arctic Circle on the north, 
nor much beyond the Tropic of Cancer on the south. In this 
family belong all the fishes known as carp, dace, chub, roach, 
bleak, minnow, bream, and shiner. The essential character of the 
family lies in the presence of one, two, or three rows of highly 
specialized teeth on the lower pharyngeals, the main row con- 
taining 4, 5, 6, or 7 teeth, the others 1 to 3. The teeth of the 
main row differ in form according to the food of the fish. They 
may be coarse and blunt, molar-like in those which feed on shells; 
