626 BULLETIN OF THE BUREAU OF FISHERIES. 
INFECTION OF LARGE NUMBERS OF FISH. 
In order to test the feasibility of infecting large numbers of fish, which is 
a prerequisite of artificial propagation, an extensive experiment, in which 
over 25,000 fish were employed, was made at the substation of the Bureau of 
Fisheries at La Crosse, Wis., in November, 1907. Seven species of fishes and 
glochidia from four species of Lampsilis were used in the experiment. The 
fishes, with the exception of the German carp and the bullheads, were success- 
fully infected and retained in the tanks of the station for over two months, when 
they were liberated in the west channel of the Mississippi River at that place. 
The experiment completely demonstrated the possibility of making infections 
successfully on a large scale, and of retaining the fish until near the close of 
the parasitic period. 
In November, 1908, a similar experiment was carried out at the station 
of the Bureau at Manchester, Iowa, where about 12,000 large-mouthed black 
bass and crappies were infected with the glochidia of several species of Lampsuilis. 
The fish were kept at the station for one month and then placed in the Maquoketa 
River between two dams. As the species of mussels used in the experiment in 
all probability do not occur in that stream, the results of the work may be 
determined if we succeed in reclaiming any of them at a future time. 
During the fall and winter of 1908-9 infected fishes were put into ponds in 
the neighborhood of Columbia, Mo., where we are absolutely certain that the 
species of mussels used do not occur, and where there is every reason for the 
expectation of subsequent reclamation. The latter experiments should yield 
valuable data on the rate of growth. 
