THE GERMAN CARP IN THE UNITED STATES. 531 
darker in its posterior half; the rays themselves are of about the same 
color. The anal is yellowish-red, while the pectoral and pelvic fins 
are grayish or yellowish, tending to red toward their tips. The upper 
lobe of the caudal fin is of about the same color as the dorsal; the 
lower lobe has a lighter, yellowish cast, with more or less red, especially 
toward the end. 
The coloration is influenced by the age of the fish, the character of 
the water in which it lives, its nutrition, the season of the year, its 
sexual condition, and by the other conditions of its environment. 
Seeley (1886, p. 97) states that unsymmetrical coloring is sometimes 
found and that a fish may have glittering golden stripes on one side of 
the body and pale steel blue on the other. Sometimes typical carp are 
black, bluish, green, red, golden, silvery, or even white, and Doctor 
Fatio records that he has kept in confinement carp which were origi- 
nally green or golden, but which became colorless in an opaque vase. 
It is not an unusual thing to see in carp that have died out of water 
a reddish suffusion, especially marked in the fins, probably due to the 
congestion of blood in the capillaries as the circulation is stopped. 
In common with the other members of the family, the mouth of the 
carp is without teeth, the only organs of this description being the 
blunt, knob-like structures lying on the pharyngeal bones in the back 
part of the mouth, or ‘‘throat.” These are entirely for grinding 
food, and, as is obvious both from their position and shape, are of no 
use in grasping, this function being performed by the so called lips. 
The alimentary tract is comparatively long, but uncomplicated; the 
stomach is a simple tube not sharply differentiated from the esophagus 
and without a blind sac, while the intestine has no pyloric appendages. 
The entire alimentary tract from the beginning of the stomach?” is 
usually two to two and one-half times as long as the body. The air 
bladder is large, with tough, thick walls. A transverse constriction 
divides it into two parts; the posterior of these is the smaller and 
ends in a rounded point, while the anterior portion is larger and has 
its base somewhat bilobed. 
RACES AND VARIETIES. 
* 
The great range and frequency of variation in the carp is undoubt- 
edly largely due to its domestication or semidomestication since early 
times. As is to be expected, this has resulted in the naming of a large 
number of varieties or races. In Europe, where carp culture is car- 
ried on systematically, these races are kept pure and true, so far as 
possible; but in this country no attention has been paid to them, at 
least in recent years, so that we need not treat them in detail here. 
Those interested in the subject will find an exhaustive account in the 
contribution entitled ‘‘ Uber Karpfenrassen,” by Dr. Emil Walter, in 
a The position of the thoracic septum is here taken as the beginning of the stomach. 
