POMOTIS VULGARIS. 9 



of the abdomen backwards. The gall-bladder is small, pyriform, and the bile is of pale colour. 

 The stomach is broad, tolerably large, though short ; the pyloric portion begins near its middle, and 

 the sphincter at the pylorus is well marked. The small intestine is capacious, and makes several 

 convolutions before it ends in the rectum ; there are eight coscal appendages. The air-bladder 

 is large, broad, full in front, and slightly subdivided into pouches ; it is smaller behind, and 

 prolonged in two horns for some distance along the sides of the inter-spinal bones of the anal fin. 

 The kidney is large, though the urinary bladder is small. 



Habits. This fish prefers the clearest waters. In the spring of the year the 

 female prepares herself a circular nest, by removing all reeds or other dead 

 aquatic plants from a spot of a foot or more in diameter, so as to leave bare 

 the clean gravel or sand ; this she excavates to the depth of three or four inches, 

 and then deposits her spawn, which she watches with the greatest vigilance ; and 

 it is curious to see how carefully she guards this nest against all intruders ; in 

 every fish, even those of her own species, she sees only an enemy, and is restless 

 and uneasy till she has driven it away from her dwelling-place. We often find 

 groups of these nests placed near each other, along the margin of the pond or 

 river the fish inhabits, but always in very shallow water ; hence they are liable 

 to be left dry in seasons of great drought. These curious nests are most fre 

 quently encircled by aquatic plants, forming a curtain round them, but a large 

 space is invariably left open for the admission of light. 



Geographical Distribution. The Pomotis vulgaris is found in the great 

 Northern lakes, the Atlantic States from Maine to Florida ; and, according to Dr. 

 Kirtland, in the tributary ponds and streams of the Ohio River. 



General Remarks. In giving such a wide geographical range to this animal 

 the identity of the Northern and Southern animal is presupposed, and of this iden- 

 tity I have little doubt, after the comparison and examination of hundreds of indi- 

 viduals. It is true, if we take a single Northern and a single Southern specimen 

 for comparison, diff"erences may be observed between them that might lead us to 

 believe they were of difi"erent species ; but in a comparison of many, these apparent 

 differences are confounded or lost. We have then, in this instance, as in that of 

 the Perca Jlavesceus, an animal widely extended in our fresh waters, both North 

 and South, having certain minor differences in different regions, but agreeing per- 



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