Dr. Walker makes a signal contribution in gathering together all available information on the dragonflies of Canada and Alaska. The order as a whole and the Zygoptera are covered. The treatment is not confined to taxonomy and geographical distribution, but includes data on habitats, seasons of adult life, and brief notes on habits when these are available.
Edmund M. Walker (1877-1969) joined the Department of Biology at the University of Toronto in 1904, rising to become the head of zoology in 1934. He was also Professor of entomology in the university's department of Zoology from 1906 until his retirement in 1948.