REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXXI 



rare forms, one of considerable interest being Trochosphcera, originally 

 described from China and recently found in the Illinois River. An 

 extended illustrated report on the rotifers is in preparation. 



In addition to his other duties Professor Ward was engaged in the 

 collection and study of the parasites infesting fish. 



Dr. Snow gave attention to the determination of the microscopic 

 aquatic plants of the neighborhood, esi)ecially those occurring in the 

 plankton. By means of cultures the identification of many species was 

 greatly facilitated, and species were found in the plankton that would 

 otherwise have been overlooked. Experiments were conducted showing 

 the rate of growth of the lower foims of algtie, and man}- interesting 

 observations were made on tbese important constituents of the plankton. 

 During the season 130 species were noted, of which 84 were found in 

 the plankton, as before stated. 



Mr. Pieters's inquiries were directed to the aquatic plant life in the 

 harbor of Put-in Bay, East and West harbors. Portage River, and 

 Sandusky Bay, and consisted in i)art in making an inventory of the 

 plants and in part in a determination of the laws of their distribution. 

 Intimate relations exist between the water-plants and the fish. 



During Angust, September, and October, Dr. Kendall and Mr. Marsh 

 made collections of the fishes of the Put-in Bay region and other ])arts 

 of the lake, studied their food habits, and collected parasites and the 

 contents of fishes' stomachs. Forty-two species of fish were detected 

 at Put- in Bay, and over 700 stomachs, representing 21 species, were 

 examined. Efforts to secure young white-fish with shore seines, small- 

 mesh gill nets, and other apparatus were unsuccessful. 



With slight modifications the hatching-room at the station was found 

 to be well suited for laboratory purposes, being commodious, light, and 

 sui)plied with gas and running water, as well as close to the dock. The 

 diversity of the surroundings makes the Put-in Bay region an excellent 

 place for the study of important geneial problems pertaining to the 

 fisheries of the Great Lakes. As a location for summer work it has 

 unusual advantages, and arrangements have been made for the renewal 

 of the investigations during 1899. There is, however, no deep water 

 near Put-in Bay, and this is a drawback to studies of the i)lankton and 

 of the life-history of the white-fish and some other species. Should it 

 be determined to establish a permanent biological station on tlie lakes, 

 a more favorable site might be found, but a decision on this matter 

 must depend on an examination of other regions. 



THE SEBAGO LAKE BASIN. 



Sebago Lake ranks second in size among the many large lakes of 

 Maine, and from the fish-cultural, angling, and scientific standpoints 

 is one of the most interesting bodies of water in the United States. 

 It was from this lake that (4irard, in 1852, received the specimens of 

 landlocked salmon on which he based his description of Salmo sebago, 

 a fish which has since come into great prominence on account of its 

 sui»erioi' game and food qualities, and has been extensively propagated 



