From 1896 to 1900 he worked in Java .
After getting his PhD from Gottingen University he had a teaching positions at Johns Hopkins University ( 1891 - 1895 ) where he was director of the herbarium .
From 1896 to 1900 director worked in Java .
After getting his PhD from Gottingen University he had a teaching positions at Johns Hopkins University ( 1891 - 1895 ) where he was director of the herbarium .