THE FAIRPORT FISHERIES BIOLOGICAL, STATION. 403 



From the account of the operations of mussel propagation it is seen that the supply 



of fish for use in mussel propagation is obtained chiefly by seining in the public waters. 



In the spring after the heavy floods there are many overflow ponds near the course of 



the rivers which are filled with water and fish during the flood and which are left isolated 



as the water recedes. Under natural conditions these ponds will dry up and the fish will 



die. In connection with the work of mussel propagation some of the overflow ponds are 



seined out and such fish as are suitable for infection with mussels are used in that work. 



These and other fish that are taken are then liberated in the main course of the river; 



thus a double object is accomplished in the reclamation of fish, which would otherwise 



be lost, and in the infection with glochidia of mussels. During the past fiscal year 66,645 



adult fish were reclaimed in this way. While this reclamation work, as carried on at the 



Fairport station, is incidental to propagation work, the benefits are of great importance 



and would in large part justify the entire expense of the field work in propagation. 



The Bureau also carries on an extensive work in the reclamation of fish which is not 



connected with this station. 



INA/ESTIGATIONS.o 



STUDIES OF MUSSELS. 



The investigations relating to the natural and artificial propagation of mussels have 

 already been referred to in connection with the work of propagation. Such experiments 

 and observations are those which have received the principal attention of the permanent 

 staff continuously and which have been most productive of results. The systematic 

 study of conditions of natural infection, the careful experimental observation of artificial 

 infections of mussels on various species of fish, the systematic study of glochidia, the 

 investigation of the early or juvenile life history and distribution of juveniles, the rate 

 of growth of mussels, the structure of shell and conditions affecting its abnormalities, 

 the formation of pearls, the chemical and physical properties of mussel shell, the utiUza- 

 tion of mussel meats — these are some of the problems which have been engaged upon, 

 and several of which have been reported by the different investigators. As illustrations 

 of the nature of results gained, there may be mentioned the accumulation of observations 

 making easier the identification of mussels in the glochidium stage, the discovery of the 

 particular relations existing between mussels and fishes, there being a restricted group 

 of hosts for each species of mussel, the discovery of an additional case of development 

 without parasitism, the discovery of important enemies of the juvenile mussels, the 

 observation that rate of growth in some important species is more rapid than had ever 

 been supposed, the observation that interruptions of the growth of mussels may cause 

 effective flaws or faults in the structure of the shell, and the demonstration that mus- 

 sels may directly absorb nutritive substances from solution in the water. 



Mention must be made of the investigation of streams and lakes productive of 

 mussels. In some cases the studies have been in the nature primarily of economic 

 reconnoissances, in others more particular attention has been given to the facts and 

 problems of distribution and ecological relations. The Kankakee, the Maumee, the 



« In so brief a summary of the investigation it will not be necessary or practicable to associate each topic with the name of 

 an investigator. It is. however, desired to mention the names of those whose studies have contributed to the success of the sta- 

 tion. Profs. George Lefevre, W. C. Curtis, and Charles B. Wilson, H. Walton Clark. Dr. A. D. Howard, Thaddeus Surbcr, 

 A. F. Shira, Prof. F. D. Barker, J. F. Boepple, J. B. Southall, Ernest Danglade, E. P. Churchill. F. B. Isely, W. I. Utterback, 

 and the present writer have appeared as authors of published reports emanating from this laboratory. Among others who 

 are now conducting experiments and investigations are Emerson Stringham, H. L. Canfield, Dr. A. S. Pearse, R. H. Lioktns 

 (with Prof. H. B. Ward), and Miss Susanne Parsons (with Prof. F. D. Barker). 



