REPORT OF COMMISSIONER OF FISH AXD FISHERIES. XV 



I)Ose of ascertaining facts connected with the spawning of the fish, the rate 

 of growth of the young, the localities preferred by them, &c. Professor 

 Yerrill and his parties wese engaged also throughout the summer in 

 making collections along the shores at low tide, as also in the constant 

 use of the dredge and the towing-net. 



One important question connected with this investigation, in addition 

 to determining the character of the food available for the fishes, was to 

 ascertain its comparative abundance, a great diminution- or failure of 

 such food having been alleged as one cause of the decrease of the 

 fisheries. Care was therefore taken to mark out the position and ex- 

 tent of different beds of mussels, worms, star-fishes, &c., at the sea-bot- 

 tom, and by straining the water at various depths and at the surface, to 

 ascertain the amount of animal life therein. Temperature observations 

 were also repeatedly taken and recorded, especially from the revenue- 

 cutter Moccasin, under command of Captain Baker. 



Having ample facilities at hand for making zoological collections, the 

 opportunity was embraced to secure large series, not only for the na- 

 tional museum at Washington, but also for other establishments; and 

 a sufficient quantity was gathered to supply sets (as soon as they can be 

 fully elaborated) to the various colleges and other public institutions 

 throughout the country. Large numbers of fishes, especially of the 

 more showy kinds, such as sharks, skates, rays, &c., in which the w^aters 

 abound, were secured for a similar purpose, and a partial distribution to 

 colleges and societies has already been made of the dui)licates of this 

 portion of the collections. The occasion was also embraced by several 

 gentlemen to make special collections for establishments with which 

 they were connected. Among them we may mention more particularly 

 Professor Jenks, in behalf of Brown University ; Professor Hyatt, for 

 the Boston Society of Il^atural History ; Professors Smith and Yerrill, 

 for Yale College ; Professor Todd, for Tabor College, Iowa ; Doctor Far- 

 low, for the Botanic Garden at Cambridge, &c. Facilities for such en- 

 terprises were always gladly furnished. 



With a view of exhibiting the character of the fishes of the region 

 explored, and determining their rate of growth, an experienced photog- 

 rapher accompanied the party, who, in the course of the summer, made 

 over two hundred large negatives of the species in their different stages 

 of development, at successive intervals throughout the season. These 

 constitute a series of illustrations of fishes entirely unequaled ; forming 

 an admirable basis for a systematic work upon the food-fishes of the 

 United States, should authority be obtained to prepare and publish it. 



Among gentlemen interested in science who visited Wood's Hole dur- 

 ing the summer for a greater or less period of time, either with special 

 reference to co-operation in the work of the commission, or on account 

 of the interest experienced in such investigations, maybe mentioned 

 Professor L. Agassiz, of Cambridge ; Professor J. W. P. Jenks, of Brown 

 University; Professors Yerrill, Smith, D. C. Eaton, William D. Whitney, 



