Dr. Raymund Lull Zwemer, 79, a biologist who was a former college professor and State Department official and was active in professional organizations, died of cancer Monday at Montgomery General Hospital. He lived in Silver Spring.

Dr. Zwemer came to Washington in 1944 to join the State Department. He was associate chief of the State Department's cultural cooperation division, and executive director of the State's interdepartmental committee on science and cultural cooperation between 1944 and 1947.

He then spent three years as executive secretary of the National Academy of Sciences before serving as chief of the science division of the Library of Congress from 1950 to 1955. He then worked for UNESCO before returning to the State Department in 1958. He was an assistant science adviser until leaving three years later.

Since that time, Dr. Zwemer had been active as an editor and official of scientific organizations, including the American Association of Anatomists and the Federation of American Societies for Experimental Biology.

He also had been a scientific adviser to various Latin American governments, a delegate to a Pan American Congress on Endocrinology, and UNESCO representative to the World Health Organization.

Dr. Zwemer was born in Bahrain to American missionary parents. He was a 1923 graduate of Hope College in Michigan and earned a doctoral degree in zoology at Yale University. He taught anatomy at Columbia University's medical school for 16 years before coming here in 1944.

Survivors include his wife of 52 years, Dorothy, of Silver Spring; two sons, Raymund W., of Walnut Creek, Calif., and Theodore L., of Silver Spirng; two daughters, Suzanne Z. Visser of Plymouth, Mich., and Jane Z. Koeser of Poolesville; three sisters, Elizabeth Z. Pickens of Annisquam, Mass., Amy Ruth Violette of Alexandria, and Mary Z. Brittain of London, England, and 12 grandchildren.