;l. CYPRINIDiE. 
145 
whicli to distiugnisli genera and species. Onr genera are mostly very 
closely related, and are separated by characters whicli, although reason- 
ably constant, are often of slight structural importance. From time to 
time, different authors have proposed to throw most of these groups into 
the genus Leuciscus, a procedure which, without further discussion, may 
be said to have always led to confusion. The spring or breeding dress 
of the male fishes is often peculiar. The top of the head, and often the 
fins or various portions of the body, are covered with small tubercles, 
outgrowths from the epidermis. The fins and parts of the body in the 
spring males are often charged with bright irigment, the prevailing color 
of which is red, althorrgh in some genera it is satin-white, yellowish, or 
black.* 
{Cyprinida;, part, Giintlier, vii, 25-339.) 
* Dorsal fin short, without develojietl spine, 
t Air-bladder surrounded by many convolutions of the very long alimentary cauai. 
{CamposioMivce.) 
A. Teeth 4-4, or 1, 4-4, 0, with oblique grinding surface and slight hook ; peri- 
toneum black. 
Campostoma, 71. 
tt Air-bladder above the alimentary canal ; teeth one-rowed. (Chondrostomincc.) 
1 Intestinal canal elongate, more than twice the length of the body; teeth with 
grinding surface well 
developed ; peritoneum 
usually black. 
B. Jaws each with a conspicuous, broad, straight-edged, horny plate ; teeth 4- 
5, stout, bluntish, hook- 
ed, and short. 
Acrociiilus, 72. 
BB. Jaws without horny plate. 
C. Teeth 6-6, strongly compressed, kuife-shai)ed ; pseudobranchiaj none ; ru- 
dimentary caudal rays 
greatly developed; 
sc.alcs very small. 
Orthodox, 73. 
* No progress can be made in the study of these fishes without a careful examina- 
tion of the teeth. The xiharyugeal bones in the smaller species can be removed by in- 
serting a pin or a hook through the gill-oi)ening, under the shoulder-girdle. The 
teeth should be carefully cleaned with a tooth-brush, or a .jet water, or a pin, and 
may be examined by any small lens. In most cases a inincipal row of 4 or 5 teeth 
will be found, in front of which is sometimes a set of 1 or 2 smaller ones. The two 
sides are not always symmetrical. “Teeth 4-4” indicates a single row of 4 on each 
pharyngeal bone. “ Teeth 2, 4-5, 1” indicates 2 rows of teeth on each side — on the one 
side 4 in the priucii)al row and 2 in the lesser, on the other side 5 in the main raw 
and 1 in the lesser. In the Levciscine genera these teeth, or the principal ones, are 
raptatorlal, that is, hooked inward at their tips. A grinding or masticatory surface is 
an excavated space or groove usually at the base of the hook. A flattened or bev- 
elled edge sometimes simulates a masticatory surface, and in some of the species the 
grinding surface is very narrow and confined to but one or two of the teeth. In all cases 
where the number of teeth is given in the specific descriptions following, t*his number 
has been verified on typical examples either by Prof»j6sor Cope or the writers. 
Bull. Nat. Mus. No. IG 10 
