Jahn, E., circa 1927-1942

Hagelstein's correspondence contains lists of specimens of both diatoms and myxomycetes as well as formal and informal views from the most renowned scholars of both fields. In his capacity as President of the New York Microscopical Society, he exchanged information with like groups throughout the world. The McKinley and Morris folders in Subseries A contain information about Hagelstein's financial investments and have informative value for students of that aspect of the era. More information on this historical aspect is found in Series 4: Manuscripts where backs of his Lecture Notes on Diatoms, are the February, 1904 dailies of the "Wall Street Journal Electric News Ticker." All photographs which originally were enclosed in correspondence have been removed and placed into Series 6: Photographs.