PERCA FLAVESCENS. 5 



large, short coecal appendages. The liver is small, and seems but a single mass, as there 

 are no marks of separation into lobes. The spleen is short, flattened, narrow, and of a very 

 dark colour. The air-bladder is large, and extends the whole length of the abdominal cavity ; 

 it is of a conical shape, broad in front, and pointed behind, with a beautiful vascular ganglion on 

 its inferior surface within. The ovaries are large, and united closely together behind. The kidneys 

 are large, but the urinary bladder is small. 



Habits. The Perch, is a voracious animal, although its teeth are but small ; it 

 is solitary in its habits, for even in ponds and rivers, when most abundant, it is 

 never seen in shoals, like many other fish, but each one seeks its own dwelling- 

 place. In cold weather it is found in deep water, but in the summer months it 

 may be seen swimming slowly, and most generally against the current of the 

 stream ; suddenly it stops and remains stationary for a minute or two, and often 

 in a position almost perpendicular, with its head near the ground, as if seeking 

 nourishment; it now suddenly darts forward, swims rapidly for some distance, 

 and then again comes to a stand. In July and August it approaches the surface, 

 allured, doubtless, by grasshoppers and such other insects as may fall into the 

 water ; and at this time it rises to the fly, though in general it is baited with 

 worms. The flesh is white, firm, and delicate, and is much esteemed. 



Geographical Distribution. This fish has a very widely extended geograph- 

 ical range. It has been observed in nearly all the Atlantic States ; in the great 

 Northern lakes ; and, according to Professor J. P. Kirtland, of Cleaveland, it has 

 lately found its way into the tributaries of the Ohio River.* 



General Remarks. Previous to the time of Cuvier, all ichthyologists sup- 

 posed the American Perch to be identical with, or at least a simple variety of, the 

 European, so great is the resemblance between them ; Cuvier, however, not only 

 proved it to be a distinct species, but went still further, and described the 

 several varieties of the American Perch as so many different species ; and in this 

 he has been followed by several naturalists. But it should be remembered 

 that those fishes that are common to a geographical region of great extent are 

 subject to individual variations, which can only be recognized by a comparison 



* Bost. Journ. Nat. Hist., vol. v. p. 337. 



