Born in Cadiz, Spain, Andrew Fernando Holmes received his Doctor of Medicine degree from the University of Edinburgh in 1819. He later tought both botany and chemistry at the Montreal Medical Institution, which in 1929 became the Medical Faculty of McGill. Holmes was the first professor of botany in 1829 and the first dean of the medical faculty in 1854.
Holmes collected extensively on Mount Royal and in the vicinity of Montreal in the 1820s, being an active member of the Montreal Natural History Society. His herbarium of 600 sheets was presented to McGill in 1856 and became the nucleus of the present herbarium.