MIGRATION OF. THE WHITE-FISH. 511 



other seasons of the year, and the lish sought the shore where the splashing on the beauh and 

 sand-bars supplied the water with the requisite amount of air, just as other species ol' this family 

 of fishes delight in rapids and falls, because the breaking up of the masses of water sHpi)lics it 

 with a large amount of respiratory gases. 



"In waters like Lake Erie, where, according to the Lake Survey, the temperature attains as 

 high as 75°, the White-fish seek the cooler deep waters in the summer, and 1 have not learned of 

 a migration upon the shore at any ijoint, they, perhaps, preferring a less amount of aeration to a 

 high degree of heat. 



"The fact that in the month of August the White-fish of thf Sault Ste. Marie Eapids leave 

 the river entirely, and do not return until in September, weakens the force of the theory that the 

 aeration of the water is the necessity that brings them to the shore of the lake in the summer. 



"Professor Agassiz, in his tour of the north shore of Lake Superior in 1849, found the White- 

 fish scarce along the shore and at the rapids in the month of August. Among the Apostle 

 Islands, Lake Superior, and in most of the deeper portions of the lakes, no scarcity is observed at 

 this season of the year. At the rapids, they so entirely abandon the locality in August that the 

 supply offish for the hotels has to be obtained from Poiut Detour, at the head of Lake Huron. 



"It was a disputed ])oint among the Waukegan fishermen whether the migration was directly 

 in from deep water or along the shore. The fact that, in some instances, the schools of fish struck 

 the nets at one point, and afterwards entered the nets iu succession along the line of the shore, 

 was thought by many to prove a littoral migration. But the fact was that, in all likelihood, the 

 advance portion of a school would touch the shore at some point and then move in either direction 

 along its line. 



"The presence of large White-fishes in numbers at certain localities on the north shore of 

 Lake Michigan, of a size that are never taken at other parts of the lake, yrould indicate a local 

 habit, with lao disposition to range through long distances. Another observation sustaining the 

 probability of this is the fact that there are many localities on the Lakes where the pound-nets, a 

 few years ago, found prosperous fishing, and in the first few years took the White-fish in great 

 abundance, but found afterwards a decrease from year to year until the, locality was abandoned, 

 while fifty miles away the business still continued successful. The well-known local instincts of 

 the Salmon would, to a slight extent, confirm the probability of like instincts in its related genera. 

 The fact that certain types of the White-fish are peculiar to particular localities, as the north 

 shore of Lake Michigan, the Sault Ste. Marie Eapids, Bachewauna Bay, on Lake Superior, indicates 

 a local habit through many generations until certain characters of a race have become established. 

 The same fact has been stated for the shad on the Atlantic coasts. Some observations, made in 

 1871, perhaps indicate the opposite of all the foregoing statements. 



" In the early part of the season there had been very few fish caught on the west shore of Lake 

 Michigan, between Chicago and the Door Islands. South of Chicago, at the mouth of the Calumet 

 Eiver, the run of White-fish was in excess of anything had for years. But, about the 15th of June, 

 the schools of fish left Calumet, and a few days later there was a decided, improvement iu the 

 catch at Evanston. About June 22, the lifts at Waukegan began to be heavier than they had 

 been before. During the first week of July the fishing was observed to improve at Milwaukee, 

 Manitowoc, and Bailey's Harbor, and, a little later, at the Door Islands. The coincidence in dates 

 rather indicated a probability that the same schools of fish that clogged the nets at Calumet 

 during six or seven weeks had ranged northward along two hundred and sixty miles of coast. 

 Still, the effect on the fishing would have been the same if it had been the migrations of schools 

 of fish from deep water at these points in to the shore. In order to obtain a definite knowledge of 



