LAMPREYS AND FISHES 



and then mate again. At each mating the female lays 20 to 

 40 eggs, and matings are kept up at intervals for 2 to 4 days 

 until 25,000 or 35,000 eggs are laid. In streams which 

 flow into Cayuga Lake the lamprey spawning season lasts 

 through April, May and June. The worm-like eyeless and 

 toothless larvae stay in the nest for a few weeks after hatching, 

 and then burrow into the sand, living like worms in the stream 

 banks until they are about five inches long, when they trans- 

 form to the adult shape. Adult lampreys live wholly upon 

 fish blood except during their actual breeding season. They 

 are ravenous for a long time before this and kill hundreds of 

 fish, which appear floating upon the surface with large holes 

 bored through their sides. The upturned body of a dead fish 

 with its quota of lamprey holes is a familiar sight in more 

 than one of the New York Finger Lakes. 



Size. — Length of adults 2 to 3 feet. 



Distribution. — Lampreys which live entirely in fresh water 

 are found in the Great Lakes and their tributaries and in 

 some streams in New England and the middle Atlantic states. 

 Along the Atlantic coast large sea lampreys go up the streams 

 to spawn. They are found in the Merrimac River, the Con- 

 necticut, the Delaware, and some of the streams of Long 

 Island. 



Fig. 271. — Brook trout, Salvelinus fontinalis. 



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