EXPERIMENTS IN THE CULTURE OF FRESH- WATER 



MUSSELS. 



By ARTHUR DAY HOWARD, 

 Assistant, I'. S. Bureau of Fisheries. 



CONTENTS. 



Part- 

 Introduction 63 



Methods and plan of investigation 64 



Observations on growth of juvenile mussels 66 



Growth in floating crates 68 



Growth in aquaria, tanks, and troughs 72 



Growth in cement-lined ponds 74 



Growth in earth ponds 77 



Growth in pens 77 



Structure and development of juvenile mussels 78 



Habits and habitat of juvenile mussels 80 



Discussion and application of results 83 



Artificial propagation 84 



The cultural method 84 



Protection 84 



Planting 86 



Commercial possibilities 86 



Literature cited 87 



INTRODUCTION. 



The coming of fresh-water mussels to a position of commercial importance in 

 America resulted in a special demand for information as to methods of propagating them. 

 In response to this demand the U. S. Bureau of Fisheries undertook an extensive inves- 

 tigation of the commercial fresh-water mussels. This led to the adoption of a method 

 of propagation that promised effectively to increase the supply of mussels. This method, 

 briefly, is the infection of suitable fish with the young mussels in the parasitic stage. 

 These fish are then released to spread the mussels at large under natural conditions. The 

 investigations have been continued for the purpose of extending the application of the 

 methods now in use, the testing of new methods, and to secure more complete information 

 on the life history of the mussels used in pearl-button manufacture. 



Since Leydig's (1866) discovery that the young fresh- water mussels are parasitic 

 on fish, many attempts have been made to raise them in captivity. No particular 

 difficulty has been experienced in carrying certain species through the parasitic stage, 

 but up until the time of the present investigation there seem to have been no records 

 of the rearing of these under observation through what is called the juvenile stage. 



63 



