XCVI REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



wonderful of the natural attractions of America. It is approximately 

 circular in shape and about 5 miles in diameter. It lies in the top of 

 Mount Mazama, and is comiDletely encircled by a bold escari^ment 

 rising from 500 to 2,000 feet almost vertically from the water's edge. 

 So steep are the walls that in only a few places is it possible to descend 

 to the lake. Crater Lake is the deepest American lake, and one of the 

 deepest in the world. The greatest ascertained depth is 2,000 feet, a 

 large part of the bottom being practically a level floor of this depth. 

 With a few limited exceptions there is practically no shore and scarcely 

 any shallow water, the surrounding walls extending vertically beneath 

 the water to a depth of several hnndred feet. In Eagle Cove on the 

 south side of the lake, in Cleatwood Cove on the north side, and about 

 Wizard Island are found the only considerable areas of shallow water, 

 the depth ranging from 2 to 100 feet; and, in the absence of streams 

 flowing into the lake, the best conditions required for spawning-beds 

 would probably be furnished at these places. 



The water was ascertained to be sufliciently pure and of proper tem- 

 perature for trout, and to contain a fairly abundant supply of fish-food, 

 consisting chiefly of small crustaceans, insect larva>, and mollusks. 

 While the conditions do not seem favorable for the existence of an 

 abundant fish life in this lake, it is probable that a limited number of 

 tront would be able to maintain themselves in it, especially the species 

 of black-spotted trout found in Lake Tahoe {ISalmo mykiss henshawi). 



COAST RIVERS OF CALIFORNIA. 



In May, 1897, Dr. Charles H. Gilbert, with four assistants from 

 Leland Stanford Junior University, was engaged to make an ichthy- 

 ological canvass of the coastal streams of California, and at the close 

 of the year the inquiry was still in progress. The object of the investi- 

 gation was to study the fishes of the difterent streams with reference 

 to their distribution, abundance, spawning habits and grounds, etc., 

 particular attention being paid to the species of economic value. 



FLORIDA. 



In October and ]!>J^ovember, 1896, certain investigations were carried 

 on in the coastal waters of Florida in response to a resolution of the 

 United States Senate, dated February 15, 1895, requiring the Com- 

 missioner to make an inquiry as to the extent, methods, and present 

 condition of the coast fisheries of the State, especially the sponge and 

 oyster fisheries. Prof. B. W. Evermann and Dr. W. C. Kendall repre- 

 sented this division in the party sent by the Commissioner to make the 

 necessary examinations. Special inquiries were made at Key West, 

 Biscayne Bay, Tampa, Tarpon Springs, and other i)laces, having for 

 their object a study of the natural history of the various species of com- 

 mercial sponges with reference to the causes of the decrease in their 

 abundance and the possibilities of artificial propagation; also a deter- 



