368 BULLETIN OF THE BUREAU OF FISHERIES. 



For this reason, in February, 1909, the results obtained and the importance of the 

 subject were laid before President Roosevelt, who decided that a joint investigation 

 between the Gratwick Laboratory and the Bureau of Fisheries should be undertaken. 

 The Commissioner of Fisheries, Hon. George M. Bowers, detailed Mr. Millard C. Marsh 

 as the representative of the Bureau to cooperate with the State. Facilities were at once 

 afforded for a detailed investigation at one of the Government fish hatcheries where the 

 disease was endemic. 



The first summer's work was carried out by Dr. Gaylord at this Government 

 hatchery. In the winter of 1909-10 Mr. Marsh, working at the Gratwick Laboratory 

 in Buffalo, in conjunction with Dr. Gaylord, carried out a series of experiments on 

 feeding, crowding, vitiation of water, etc. The summer of 1910 was again spent by 

 Dr. Gaylord and Mr. Marsh at the Government hatchery in question. The winter of 

 1910-11 Mr. Marsh continued the work in Buffalo. In July, 191 1, Mr. Marsh was 

 detailed for ser\'ice in Alaska and Dr. Frederick C. Busch, of the State Institute for the 

 Study of Malignant Disease, took up his part of the work. In the pathologic histologic 

 part of the work Dr. Burton T. Simpson contributed largely, having studied many 

 hundred sections and recorded important facts. The experimentation at the Govern- 

 ment hatchery has been conducted to a point where it is now possible to make the first 

 report on the studies thus far conducted into this disease. 



In this report we have attempted to determine the nature of this affection, to present 

 a well-defined picture of the disease as it occurs in hatcheries under conditions of 

 practical fish culture, to determine as nearly as possible the factors which predispose to 

 the development of the disease, and to present certain conclusions regarding its nature. 

 Identification of the agent which causes this disease we have left for future investigation. 

 How important to fish culture and how significant to cancer research future studies in 

 the more shaq^ly defined field to which this report is an introduction will prove, may be 

 easily seen from the significant facts thus far adduced. 



In our investigations and in the preparation of this report we have had assistance 

 from many persons to whom we wish here to acknowledge our indebtedness. The joint 

 investigation was begun during the incumbency of Hon. George M. Bowers as Commis- 

 sioner of Fisheries, and the resources and facilities of the Bureau were freely used by him 

 in furtherance of the mutual undertaking. Likewise, Dr. Hugh M. Smith, who as 

 Deputy Commissioner interested himself keenly in the encouragement of the work, has 

 since his recent appointment to the commissionership continued in every way to give 

 indispensable support and cooperation. The members of the fish-cultural and scientific 

 staffs of the Bureau in Washington, and superintendents and employees of stations, 

 have given much time and effort in various ways. Of the latter, Mr. C. G. Atkins, 

 superintendent of Craig Brook station, has been our chief dependence. 



The Commissioner of Forest, Fish, and Game of the State of New York, Mr. James 

 S. Whipple, and the State Fish Culturist, Dr. T. H. Bean, have furnished valuable 

 assistance by placing at our disposal facilities and material at certain of the State hatch- 

 eries. The superintendents and employees at the hatcheries at Bath, Caledonia, and Cold 

 Spring Harbor gave much direct assistance. 



