PROGRESS IN BIOLOGICAL INQUIRIES, 1938 61 
ological action in reducing the rate at which water is pumped by 
oysters. Fractionation of crude sulphate soaps has yielded portions 
both physiologically inactive and physiologically active. Studies are 
under way for the purpose of isolating, if possible, the single active 
constituent. A future study will be the determination of the part the 
physiologically imactive materials may play in the distribution and 
duration of the potency of the active portions. 
Frequently large quantities of foam are observed in ditches lead- 
ing to the river. Examination of the foam indicates the likelihood 
of its being a soap rather than a saponin. Further work is planned 
on the chemical nature and the effect on oysters of this material. 
Tests of material entering one of the sewer ditches from an over- 
flow of foam from the weak liquor storage tanks indicate that this 
material is chiefly a dilute form of the so-called “black liquor” which 
results from the digestion of the wood chips, with possibly an addi- 
tion of a small amount of soap. 
Chemical investigations are planned on black liquor samples for 
the purpose of finding whether any correlation exists between the 
alkalinity and volatile sulfide content of the various black liquor 
samples and the variations in effect on oysters exhibited by these 
samples. Fractionation of the black hquor will be undertaken, and 
efforts to develop a reliable method for the detection and determina- 
tion in river waters of constitutents of the black liquor will be 
continued. 
Tests on the physiological effectiveness of pulp-mill effluent have 
shown that storage of weak black liquor in air brings about a slow 
loss in potency. It seems that this change is chiefly in oxidation, 
since agitation in the presence of pure oxygen under pressure ren- 
dered the material physiologically inactive, whereas the effluent stored 
under hydrogen held its potency at a constant figure for periods of 
from 2 to 3 months. 
SPECIAL SURVEYS 
Under the direction of Dr. Galtsoff, a study of the sequence of foul- 
ing organisms on experimental panels exposed by the United States 
Navy at Cavite, P. I., and Guantanamo Bay, Cuba, was completed by 
G. Robert Lunz, Jr., and the report was prepared and submitted to 
the Navy Department. Preliminary experiments on the nature of 
the fouling film were carried out at Langley Field, Va. 
At the request of the United States Engineers, Dr. Galtsoff made a 
survey of oyster bottoms in Onset Bay claimed to be affected by 
dredging operations in the Cape Cod Canal. Numerous samples of 
water and oysters were taken for examination. Certain areas were 
found to be covered with recent deposits of sand and mud and con- 
tained large numbers of dead oysters. Since the examinations were 
made long after the completion of dredging operations in this section, 
the cause of the mortality of oysters could not be ascertained. 
Another survey of similar nature was made in Narragansett Bay 
at the request of the United States District Engineer in Providence. 
Fortunately, in this case, the survey was made while the dredging 
operations were still in progress. Samples of oysters were obtained 
from 16 stations on both sides of the canal. Examination of oysters 
