834. FISHES—CY PRINIDZ. 
NorE.—The student will find it necessary from the first to examine very carefally the 
teeth of these fish, as only by dental characters can most of the genera be recognized. 
The pharyngeal bones lie behind the gills, inside of and parallel with the shoulder gir- 
dle. They can be removed by inserting a pin or small hook under the shoulder girdle. 
They should be carefully cleaned, and in most cases they can be examined only by aid of a 
lens. Usuallya principalrow of four or five larger teeth will be found, in front of 
which is a set of one or twosmaller ones. The two sides are usually but not always 
symmetrical, therefore both must be examined. Thus “ teeth 2, 4-5, 1, indicates two 
rows of teeth on each side, on the one side four in the principal row and two in the 
lesser, on the other side five in the main row and one in the other. ‘* Teeth 4-4,” in- 
dicates a single row of four on each pharyngeal bone and so on. 
In most of our genera, these teeth—or the largest ones, are ‘‘raptorial,” that is 
hooked inward at the tips. A ‘“‘ grinding” or ‘‘ masticatory ” surface, is an excavated area 
in the concavity of the hook or at its base. Sometimes a lateral bevel on the edge. 
of the tooth so resembles a masticatory surface as to ‘‘ deceive the very elect” until the 
question as to its actual concavity is tested by a pin or other similar object. Sometimes 
the masticatory surface is very narrow and confined to one or two of the teeth. In the 
present state of our knowledge, the presence or absence of this surface must be taken 
as a generic character. 
ANALYSIS OF GENERA OF CYPRINIDZ. 
*Species native, with the dorsal short and without serrated spine. 
+ Intestinal canal mere or less elongate (more than twice as long as head and body) ; 
peritoneum (lining of abdominal cavity) dark ; teeth not strongly hocked, with 
grinding surface. 
a. Intestinal canal 6 to 9 times length of body, coiled around the air-bladder ; teeth 
4-4 or 1, 4-4, 0. : : 6 CAMPOSTOMA. 25. 
aa. Intestinal canal 2 to 4 times length of body, hae the air- bladder and not coiled 
around it. 
b. Teeth 5-5 or 4-5; anal fin short; scales minute ; lateral line imperfect. 
CHROSOMUS. 26. 
bb. Teeth 4-4; scales ratherlarge, _ 
c. Dorsal fin with its rudimentary ray slender, firmly attached to the first 
developed ray ; lateral line complete. 6 : HYBOGNATHUS. 27, 
cc. Dorsal fin with its rudimentary ray rather stout, spine-like, connected by 
a membrane to the first developed ray (a black spot on front of dorsal 
fin, above the base). 
d. Lateral line incomplete. ° : : : 6 PIMEPHALES, 28, 
dd. lateral line complete. ; . 5 : . HYBORHYNCHUS. 29. 
++ intestinal canal short, less than twice the length of head and body ; peritoneum 
pale; teeth well hooked. 
t Abdomen behind ventral fins, not compressed to an edge ; anal basis moderate or 
short. 
e. Lower jaw three-lobed ; the dentary bones forming the middle lobe, being united 
their whole length ; upper jaw not protractile ; teeth 1, 4-4, 1, without grind- 
ing surface. : 5 : . 0 EXOGLOSSUM. 30. 
ee. Lower jaw not three- reel the dentary bones distinct, except at their 
symphysis. 
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