BUREAU OF FISHERIES 161 
On the south Atlantic coast, although generally favorable condi- 
tions for growth are found, some beds are badly overcrowded. Ex- 
periments are being conducted to develop a method of protecting seed 
oysters from the attachment of larval oysters, barnacles, etc., so that 
Sn at be grown to marketable size as single individuals of good 
quality. 
Experimental oyster beds have also been established in South Caro- 
lina to develop methods of cultivation suitable for small oyster farms, 
from 2 to 10 acres in extent, to be leased and operated by the tide- 
water residents. The program differs from previous experiments in 
presupposing that capital requirements will be at a minimum and 
that materials, equipment, and supplies will be obtained or produced 
by the labor of the oyster farmer himself. 
At the Pensacola, Fla., laboratory an experimental oyster farm is 
being established to determine rates of growth and fattening, pro- 
ductivity annually per unit of bottom, and costs of production. The 
results will be compared with those of similar projects conducted on 
the Atlantic coast. A program of oyster planting and of rehabilita- 
tion of exhausted natural beds is also being conducted from this 
laboratory. 
Investigations carried out at the Yorktown laboratory demon- 
strated that pollution of the river by pulp-mill wastes has brought 
the decline of the oyster fisheries. During the past year intensive 
chemical studies were carried on for the purpose of determining the 
particular chemical or chemicals in the pulp-mill effluents which are 
responsible for the altered physiology of oysters. An attempt will 
then be made to find a means of eliminating the harmful substances. 
Studies of the physiology of the oyster carried out at Woods Hole, 
Mass., included investigations of the phenomenon of sex reversal in 
adult oysters, experiments on the time of survival of eggs and sperm, 
and a study of respiration in relation to the carbohydrate metabolism 
of the oyster and the accumulation of elements which are important 
food constituents of oyster meat. 
LAW ENFORCEMENT DIVISION 
The act of July 2, 1931, the Federal Black Bass Law regulating 
interstate commerce in black bass, is administered by this Division; 
also certain parts of the Whaling Treaty Act of May 1, 1986, giving 
effect to the various international treaties for the protection of 
whales. The Division also maintains an angler’s service, and issues 
permits to take bait fish in the District of Columbia. 
The Federal black bass law—The personnel and methods of en- 
forcement remain the same as last year. Owing to insufficient per- 
sonnel, no particular effort has been made to carry on the work west 
of the Rocky Mountains, where salmon and trout predominate. Re- 
ports of illegal interstate shipments of black bass have been investi- 
gated, producing evidence of violations of both State and Federal 
laws. A number of these cases have been turned over to the States 
for prosecution in State courts, as such action generally produces 
quick and effective results. Two cases of illegal interstate shipments 
of black bass by trucks were successfully prosecuted during the year, 
a fine of $100 and 1 day in the custody of the U. S. Marshal being 
