Pennsylvania, an outstanding student of fish tumours, worked 

 on the mechanism of vital staining and cellular degeneration. 



Investigations for the Bureau of Fisheries were carried 

 on by P. S. Galtsoff, who studied the effect of external factors 

 on survival of oyster larvae and continued to work with the as- 

 sistance of Eugenia Galtsoff on regeneration and dedifferentia- 

 ton in sponges. The work on oyster larvae was the result of 

 observations made during the survey of Long Island, which 

 showed that industrial pollution may be a factor in the failure 

 of setting of oysters in the waters along the northwestern shores 

 of the Sound. Dr. and Mrs. Charles J. Fish remained in resi- 

 dence the year around and continued their studies of seasonal 

 distribution of plankton and the identification of young fishes. 

 During the month of July (1925), O. E. Sette, Assistant in 

 charge of Fishery Industries of the Bureau of Fisheries, car- 

 ried on laboratory and field investigations of mackerel. 

 Francis Staff, Director of Fisheries in Warsaw, Poland, 

 visited the Laboratory and spent 10 days acquainting himself 

 with American fishes and methods of fishing. 



In the summer of 1926, the position of the Director of 

 the Laboratory was occupied by J. O. Snyder, Professor of 

 the Department of Zoology of Stanford University. Research 

 on mackerel was conducted by Sette; C, J. Fish started a 

 study of the life history of young cod fish. Galtsoff, with the 

 assistance of Henry Federighi and H. Richard Seiwell, initiated 

 experimental studies on the physiology of oyster feeding. They 

 gave special attention to the effect of temperature on the ciliary 

 motion of the gill epithelium (Galtsoff, 1928) and made obser- 

 vations on oyster culture in Wellfleet Harbor, Mass. Labora- 

 tory facilities were again made available to Cobb, Wilson and 

 Linton for their respective work. W. C. Schroeder, aquatic 

 biologist of the Bureau, stationed at the Museum of Compara- 

 tive Zoolog;)^ in Cambridge, worked on the life histories of the 

 Gadidae and migrations of the cod (Schroeder, 1930). 



In 1927-28, the newly appointed Assistant in charge of 

 the Division of Scientific Inquiry, Elmer Higgins, served as 

 Director of the Laboratory. He worked on the material pre- 

 viously collected by him on the life histories of shore fishes 

 of the South Atlantic states. The new fishery project initiated 

 in this period was the study of life histories of Sciaenidae, by 

 John C. Pearson. The mackerel investigation by Sette was 

 conducted with the assistance of Edward W. Bailey, Lee G. 

 Kendall, Samuel L. Leonard, James A. Halstead, and Elizabeth 

 Deichmann of Radcliffe College. 



Oyster research under Galtsoff was expanded in 1927 to 

 include observations on the effect of free chlorine on water 

 propulsion, and on sensory stimulation by chemicals. The 

 latter part was conducted by A. E. Hopkins, who continued 

 this work through the winter. Oyster cultural investigation 



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