He was made a Research Associate in Geophysics at the Woods 

 Hole Oceanographic Institution, Woods Hole, Massachusetts, in 

 1946. He came to Columbia University in 1946 as a geodesist where 

 he received his M.A. in 1948 and his Ph.D. in 1949. In 1948-49 

 he worked as Research Associate in Geology at Columbia Univer- 

 sity. He becamie Instructor in the Department of Geology, Colum- 

 bia University in 1949, Assistant Professor in 1951, Associate 

 Professor in 1952, and Professor in 1957. In 1950 he became Geo- 

 physical Consultant for the Office of Naval Research. In 1951 he 

 was made Assistant Director of the Lamont Geological Observatory 

 of Colximbia University. 



He is Chairman, Special Study Group 20, International Union 

 of Geodesy and Geophysics, and a member of the Panel of the 

 Indian Ocean Expedition of the U. S. National Committee for 

 SCOR. 



He is a member of the American Association for the Advance- 

 ment of Science, the Geological Society of America, the American 

 Physical Society, the Seismological Society of America, the Society 

 of Exploration Geophysics, ajid the American Geophysical Union. 



His principal research has involved gravity at sea, seismic 

 refraction at sea, underwater photography, soxind transmission of 

 sea water, and oceanography. 



CHARLES S. YENTSCH, Research Associate in Marine Biology, 

 Woods Hole Oceanographic Institution, Woods Hole, Massachusetts. 



Mr. Yentsch was born in Louisville, Kentucky, on September 

 13, 1927. He obtained his B.S. at the University of Louisville in 

 1950 and his M.S. at Florida State University in 1953. He was a 

 Marine Biologist, Florida State University, from 1952-53, and 

 a Biological Oceanographer at the University of Washington (Seattle) 

 from 1953-55. He joined the Woods Hole Oceanographic Institution 

 in 1955 where he has been acting in his present capacity in the study 

 of marine phytoplajikton ecology. He served in the U. S. Navy 

 from 1945-46. 



He is a member of the American Society of Limnology and 

 Oceanography and the Americaji Phycological Society. 



Mr. Yentsch has published a number of articles in national and 

 international journals on marine productivity and is well known 

 in his field. He is also an authority on the instrumentation re- 

 quired for the study of the biological processes in the sea. 



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