No. 382.] METHODS IN PLANKTOLOGY. 745 
ment increases in a remarkably large ratio the number of these 
young fish which attain maturity, for the reason that the very 
young fry are specially liable to destruction from rapacious 
enemies, storms, etc. With the use of the centrifugal machines 
for collecting the microscopic food for the young fry, they can 
be kept longer in confinement, and probably the advantage 
may be twofold, for in addition to diminishing the mortality, 
we should expect that growth would be accelerated under the 
influence of abundant food. 
The Rhode Island Agricultural Experiment Station maintains a card cata- 
logue of works upon the subjects connected with Investigations on the Plankton. 
Printed copies of the Bibliography will be sent upon application. Workers are 
requested to forward reprints of their papers. Address Biological Division, R. I. 
Experiment Station, Kingston, R. I. 
