REPORT OF COMMISSIONER OF FISH AND FISHERIES. XIII 



CHARACTER AND PROGRESS OF THE INVESTIGATION. 



The plan adopted for the inquiry was determined upon after careful 

 deliberation. The great contrariety of opinion developed in the State 

 investigations as to what should have been the best-known facts in 

 the life-history of the fishes and their associates in the sea, made it 

 necessary to study the natural history of these species as thoroughly as 

 possible, so as to havefc more complete knowledge of the facts, and con- 

 sequently better means of arriving at satisfactory conclusions. Works 

 already published upon American fishes proved to contain compara- 

 tively little of value as to the biography of the coast species ; and the 

 evidence of fishermen and others, whose judgment ought to be reliable, 

 was found to be entirely contradictory and unserviceable. A systematic 

 plan of inquiry was therefore drawn up, with the assistance of Professor 

 Gill, embracing the points in the history of the fishes information rela- 

 tive to which was desirable, and a series of questions was devised, (see 

 page 1,) answers to which, if satisfactory and complete, would leave lit- 

 tle room for future inquiry. These were printed for the purpose of giv- 

 ing them a wide circulation, and include queries in reference to the 

 local names of each kind of fish, its geographical distribution, its abun- 

 dance at different periods of the year and in different seasons, its size, 

 its migrations and movements, its relationship to its fellows or toother 

 species, its food, and its peculiarities of reproduction ; also questions 

 relative to artificial culture, to protection, diseases, parasites, mode of 

 capture, and economical value and application — eighty-eight questions 

 in all, covering the entire ground. 



As the history of the fishes themselves would not be complete with- 

 out a thorough knowledge of their associates in the sea, especially 

 such as prey upon them or in turn constitute their food, it was con- 

 sidered necessary to prosecute searching inquiries on these points, 

 especially as one supposed cause of the diminution of the fishes was the 

 alleged decrease or* displacement of the objects upon which they subsist. 



Furthermore, it was thought likely that peculiarities in the temper- 

 ature of the water at different depths, its chemical constitution, the per- 

 centage of carbonic-acid gas and of ordinary air, its currents, &c, might 

 all bear an important part in the general sum of influences upon the 

 fisheries ; and the inquiry, therefore, ultimately resolved itself into an 

 investigation of the chemical and physical character of the water, and 

 of the natural history of its inhabitants, whether animal or vegetable. 

 It was considered expedient to tmiit nothing, however trivial or obscure, 

 that might tend to throw light upon the subject of inquiry, especially 

 as without such exhaustive investigation it would be impossible to de- 

 termine what were the agencies which exercised the predominant influ- 

 ences upon the economy of the fisheries. 



As already stated, the preliminary arrangements having been made, 

 and the necessary leave of abseuce granted by Professor Henry, I left 



