PROGRESS IN BIOLOGICAL INQUIRIES, 1924 25 



tardation or cessation of scale growth in late summer and winter 

 and completed on the resumption of scale growth in the spring. 

 The diameter of the scales appeared to be a better basis for the 

 length calculations of whitefish than the anterior radius, which has 

 nearly always been used in the past for many species of hsh. 



A rather complete life history of the New York aquarium white- 

 fish is given, which includes statements as to the character of the 

 food consumed, the number of feedings, the changes in the amount 

 of food consumed, the temperature of the water in different months 

 of different years, sexual maturit3% spawning, and the rate of body 

 growth. The rate of body gi-owth of the aquarium fish is compared 

 with that of Lake Huron whitefish. The significance of each of 

 the above life-history facts, rate of growth excepted, as a factor in 

 the formation of annuli, is discussed. 



This work on the corengonina? of the Great Lakes has been car- 

 ried on in the laboratories of the department of zoology of the Uni- 

 versity of Michigan. The aid and advice of Dr. Jacob Reighard 

 has been freely given and, with the cooperation afforded by the 

 State department of conservation, has done much to promote the 

 progress of the investigations. 



MISSISSIPPI RIVER FISHES 



Investigations into the life histories and migrations of some of 

 the important food fishes of the Mississippi River were conducted 

 by R. L. Barney, director of the Fairport laboratory. Mr. Barney 

 left the service before the investigations were completed, but it is 

 planned to continue the work. Studies were made of the life history 

 and spawning habits of the lake sturgeon {Acipensei' rubicundus) , 

 the shovelnose sturgeon {ScapMrhynchus platyrhynchus) , and the 

 sheepshead {Aplodinotus grunniens) . Extensive collections of scales 

 and otoliths from the sheepshead were prepared for examina- 

 tion, to be used in a study of the age, rate of growth, and age at 

 maturity. 



Other researches bearing on Mississippi River fishes have been 

 conducted at the Fairport hatchery and will be described in the 

 section dealing with investigations pertaining to fish-cultural opera- 

 tions. 



PACIFIC COAST AND ALASKA 

 ALASKA SALMON 



The red-salmon fisheries located in Bristol Bay and along the 

 Alaska Peninsula are among the most valuable of the fishery re- 

 sources of the United States. On account of extensive exploitation 

 they were in real danger of serious depletion when the Alaska 

 fishery reservations were established. Administration of these 

 reservations was vested in the Department of Commerce, acting 

 through the Bureau of Fisheries. During the past year the reserva- 

 tions have been superseded by legislation which, however, leaves 

 the administration of the fisheries of Alaska in the hands of the 

 Department of Commerce. In order that regulations may })e ade- 

 quately based the bureau has undertaken an extensive investigation 

 of the various phases of the life history of these fish. Of special 



