AN ARTIFICIAL INFECTION WITH GLO- 

 CHIDIA ON THE RIVER HERRING* 



By Dr. A. D. Howard, Fairport, Iowa. 



The River Herring, Pomolobus chrysochloHs Raf., was 

 one of the first fish recognized as a restricted carrier 

 (Surber, 1913, Howard, 1912, 1914a, 1914b) of a given 

 species of mussel. During three summers or more pre- 

 vious to 1912, experiments were carried on by the U. 

 S. Bureau of Fisheries to determine some method for 

 propagating the Quadrula mussels and particularly the 

 niggerhead, Quadrula ebenus Lea, considered the best of 

 the group for commercial purposes. In this case, unlike 

 some other mussels that had been tested, a persistent im- 

 plantation of glochidia could not be obtained upon those 

 species of fish usually employed for propagation. A sys- 

 tematic search was instituted to find if possible a natural 

 host. The discovery, on the river herring, of a natural 

 infection by glochidia of the niggerhead mussel (Surber, 

 1913) seemed to solve this particular problem. 



After the finding of the parasitic relation between this 

 species of fish and mussel, attempts were made to obtain 

 artificial infections. It was planned to transport the fish 

 to an artificial pond and there to hold them after infec- 

 tion, until the glochidia should develop. Entirely nega- 

 tive results were reported owing to the immediate death 

 of the fish at the time of capture. 



This sudden dying of the fish has been ascribed to vari- 

 ous causes. The first of these to come to mind would be 

 lack of oxygen, as the fish is very active and has relative- 

 ly large gills, in a small body of water it must soon ex- 



•Contribution from the U. S. F. Biological Laboratory, Fairport, 

 Iowa. Published by permission of Commissioner of Fisheries. 



Acknowledgements are due: Messrs. A. F. Shira and Mr. H. L. Can- 

 field for helpful suggestions and assistance; to Mr. W. F. Teachout and 

 crew for their efficient conduct of operations; to Mr. Zack Nyhart of 

 Lake City, Minn., for courtesies extended. 



