He remained as assistant professor. Mamor Oguma was conferred a doctorate in 1919. Shortly after was sent to Europe and America for further studies for a period of two years in 1922.
Returning home was appointed professor of agriculture at Hokkaido University in 1929. Then director of the Marine Research Institute attached to the university to eventually become dean of its Faculty of Science. Retired (1948) and was appointed emeritus professor in 1949.