152 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



need therefore a Complete and thorough knowledge of the true object of 

 the fisheries, of the nature of fish, and of the nature of the water in 

 which th^ fish Uve, and finally of all those conditions on which the prop- 

 agation, development, and life of fish depend. 



The scientific investigations which are of imi^ortance must in the first 

 place refer to an increased knowledge of the anatomy, physiology, develop- 

 ment, characteristics, and A^arieties of fish, as well as to their distribu- 

 tion, and the probable causes of their appearing and remaining on dif- 

 ferent bottoms, and consequent uj)on this to their varying food, their 

 isolation, hydrological relations, «fec. They must also relate to the 

 spawning of fish (time, place, whether near the surface or on the bot- 

 tom), to their growth, difference of age, food, enemies, sickness, &c., de- 

 pendent on physical conditions, their daily life, their regular annual 

 migrations (caused chiefly by their desire either to seek food or to prop- 

 agate the species), to their sudden appearance or disappearance, and to 

 its causes, t&c, as also to the nature of the fishing-waters, to the plants 

 and animals contained in them as well as to their physico-geographical 

 character. In the following we shall endeavor to point out the methods 

 which should be followed in gathering all the material which is needed 

 for a thorough knowledge of our salt-water fisheries. 



§ 17. For a thorough study of the physiology, development, anatomy- 

 &c., of fish it is doubtless necessary, if its results are to answer the in- 

 creased demands of our times, that a person should ha\e leisure, so that 

 he can devote his whole time to it, and that he should be in possession 

 of all the material and scientific apparatus which are required for such 

 investigations. For some of these investigations, well-arranged aquaria 

 will be of special value. With regard to these studies the author 

 recommended, guided by the experience of foreign countries,^^ in his 

 preliminary report,^^ the establishment of a comj)lete station for scien- 

 tific investigations of the sea^"^ in a suitable place on the Bohuslan 



'^ lu France chiefly gained by the work of Coste and later by that 5'f Lacaze-Duthier 

 and in England, France, and Germany by the great public aquaria, as well as in Italy 

 by the zoological station in Naples founded by A. Dohrn and subsidized by the govern- 

 ment. (See: BiiUet'm de la soci^te iviperial zoologique cVacclimatalion. 1862, p. 107-114; 

 1863, p. XLVII-LXIII; 1864, p. 261-269; 1865, p. 533-541; 1872, p. 164-167, 268.— 

 Archives de zoologie exp^rimentel et ijeneraJe. Ill, p. 1-38. — Preussische Jahrbiicher. XXX, 

 p. 127-161— Zeiischrift fur wissenschaftliche zoologie. XXV, p. 457-480.— ff. Beta, Die 

 Beivirthschaftung des Wassers und die Erndten daraus. Leipzig, 1868, p. 236-248. — J. G. 

 Bertram, The harvest of the sea. 3d edition. London, 1873, p. 293-296.— J'. Buckland, 

 Familiar history of British fishes. London, 1873, p. XL— On the organization and 

 progress of the Anderson school of natural history at Penikese Island. Cambridge, 

 Mass., 1874.) 



16 Prelimindr Berdttelse for 1873-74, p. 71. United States Commission of Fish and 

 Fisheries. III. Washington, 1876, p. 166. 



" In the above-mentioned report the author has expressed the opinion that the 

 necessary special hydrological investigations should be carried on by persons specially 

 detailed for the purpose, who should have their headquarters at the same station.; 

 This idea, although not without its advantages, might, however, meet with consider* 

 able difficulties when carried out practically. 



