John Muirhead Macfarlane

John Muirhead Macfarlane (1855–1943) was a Scottish botanist. He was born and educated in Scotland, where he occupied several different academic positions at the University of Edinburgh before emigrating to the United States to assume a professorial chair at the University of Pennsylvania in 1893. He held this position until retirement in 1920. He played a leading role in organising and diversifying the botanical garden of the University of Pennsylvania.

Macfarlane is most well known for his first book, The causes and course of organic evolution. A study in bioenergics (1918). He also wrote many other works including The evolution and distribution of flowering plants (Apocynaceae, Asclepiadaceae), The evolution and distribution of fishes, Fishes the source of petroleum, and The quantity and sources of our petroleum supplies.