PEOGKESS IN BIOLOGICAL INQUIRIES, 19 2 7 227 



stand the chemical nature of the green-copper compound. It was 

 attempted to isolate the green substance, and for this purpose about 

 1 liter of green extract was prepared from 1,500 oysters. The inves- 

 tigation (which is not completed) shows that the green substance is 

 not a hsemocyanin, as has been suggested by some previous investi- 

 gators. Further investigations have shown that the green color is 

 not a protein compound, but has a simpler chemical composition. 



The distribution of copper in the tissues of oysters was studied 

 also. It was found that there is copper in the blood cells and in 

 the mucus that accumulates on the surface of gills and mantle. 



Effect of chemicals. — A study of the effect of salts, which consti- 

 tute the bulk of the dissolved matter in natural sea water, was made 

 by Dr. A, E. Hopkins at Beaufort, N. C. He found that salts 

 have a marked effect upon oysters when added to the water in very 

 small quantities. Similar studies are being made of the effect of 

 foreign substances in solution. In this manner it is hoped that exact 

 knowledge may be gained of the toxic effect of all substances in sea 

 water, both the dissolved matter normally present in the sea and 

 other material, such as factory waste. 



In addition, a quantitative analysis of the glycogen in oysters is 

 being made in order to learn the nutritive value of the product and 

 the conditions under which " fattening " occurs. 



Ghlorhiation. — A study of the effect of free chlorine on oysters 

 was made at the Woods Hole Station by J. B. Clancy, of Pease 

 Laboratories (Inc.), Ncav York City. Tlie method of purification by 

 chlorinated water is being adopted gradually by the industry, and 

 it is desirable to understand better the effect of free chlorine on the 

 activity of the oyster. The experiments consisted in measuring the 

 strength of the current and the shell movements of oysters kept in 

 chlorinated water, employing the methods developed by Doctor 

 Galtsoff. 



The main part of the investigation dealt with the effect of chlorine 

 on ciliary activity of the oyster. Both liquid chlorine and hypochrite 

 in the form of zonite were used. The amount of water passed through 

 the oyster was reduced by means of a mere trace of free chlorine. 

 "With a chlorine concentration of about 0.3 ppm., only about half 

 as much water passed through, while the current was stopped almost 

 entirely by about 1 ppm. Various concentrations of chlorine were 

 used to determine the amount that Avould be detrimental to the oyster. 

 It was found that a concentration as high as 50 ppm. had little, if any, 

 harmful effect. Oysters were held for two weeks in a continuous 

 flow of chlorinated water of about 0.5 ppm. free chlorine without 

 deleterious effect. After the treatment, such oysters exhibited excel- 

 lent keeping qualities. 



SEED-OYSTER PRODUCTION AND COLLECTION 



The improved method of collecting spat developed in 1926 was 

 tested again, on a small commercial scale, in Milford Harbor, Conn., 

 and at Onset, Mass. The work in Connecticut was done by H. F. 

 Prytherch; the experiments at Onset were made by Dr. Earle B. 

 Perkins, under the direction of Doctor Galtsoff. 



