He was educated at Thornbury Grammar School and Bristol University, where he studied geology and botany, writing a thesis on canker disease of willow.
In 1930, he obtained a post in the Plant Husbandry Department of the West of Scotland Agricultural College in Glasgow, where he studied diseases of oats.
He returned to England in 1944 and became assistant to Elsie Maud Wakefield, head of mycology at the Royal Botanic Gardens, Kew.
His early publications reflected his work as a plant pathologist, but at Kew he developed an interest and expertise in fungal taxonomy, with particular reference to the ascomycetes.
These field trips produced a number of significant papers, leading up to the Fungus flora of Venezuela and adjacent countries, a substantial reference work that remains a standard text today.