MILNER FISHERIES OF THE GREAT LAKES. 37 



the. lake survey, Professor S. I. Smith made extensive dredgiugs 

 in Lake Superior, working out the bottom fauna very thoroughly, and 

 discovering some fourteen new species of invertebrate life, and eleven 

 other forms previously described, distributed from the shores out to one 

 hundred and sixty-nine ftithoms in quite well-defined zones. 



In September of 1871, on receipt of the notification that the revenue- 

 steamer Andrew Johnson had received instructions to afford facilities 

 for the examination of the fauna of the lake-bottom, a small dredging- 

 outfit was received on board, and as full collections made as the stormy 

 weather of the trip permitted. 



Tbe Academy of Sciences of Chicago furnished a large part of the out- 

 fit from their stores of apparatus; and Mr. E. W. Blatchford, of Chicago, 

 supplied a quantity of lines and nets, among the rest a trawl-net used 

 by him in collecting off the coast of Florida for the museum of the 

 Chicago Academy. This apparatus, with the dredging-coUections of the 

 trip, and the entire collections made on Lake Michigan, v/as burned, 

 ■with the academy, in the great fire of that year. 



Dr. Stimpsou had previously worked up the collection, and identified 

 the species as the same as those of his dredgiugs. 



The trawl-net was used in thirty fathoms in Grand Traverse Bay, but 

 failed to take anything, as there are probably no fishes in the lakes, other 

 than the smaller species, of so little activity as to be unable to escajle 

 capture from a twelve-foot trawl. 



The dredgings were made in from twenty-six to one hundred and 

 forty-four fathoms. The small forms of life were found to be abundant 

 at all depths, and the bottom fauna was found to be quite uniform in 

 the region of the lake examined. The different dredgings have made it 

 evident that the invertebrate life of the bottom is all small forms, though 

 so abundant as to afford food for unlimited numbers of fishes. 



The stomachs of the white-fishes examined in many localities were 

 found gorged with the crustaceans and moUusks which they had found 

 in the bed of the lake. 



Li the month of August, while making the tour of the northern shores 

 of the lake, in a Mackinaw boa-t, the dredge was carried over to Torch 

 Lake, in the Grand Traverse region of Michigan. This lake is nearly 

 eighteen miles long, with an average width of two miles. It;/ outlet is 

 first through*a shallow creek, then through two connecting lakes, and 

 through a sharp and shallow rapid into the bay. Earlier in the season, 

 with a roughly-prepared map in hand, I had sounded the lake through 

 about eleven miles of its length, to determine its average depth, which 

 was found to be forty fathoms, the deepest soundings being forty-five 

 fathoms. 



The hauls of the dredge discovered the same species of invertebrates 

 found in Lake Michigan. The fishes of Torch Lake are also the same 

 as in the main lake, its transparent waters harboring none of the 

 properly river or stream fishes. 



