Scottish botanist at the University of Southern California. Anstruther Davidson published a Flora of Southern California in 1923 and also produced an account of the plants of Arizona. Born in Watten, Scotland, he attended the University of Glasgow where he received degrees in both chemistry and medicine and was named a medical doctor in 1887. Two years later Davidson emmigrated to the United States and settled as a medical practitioner in Los Angeles. A dermatological specialist, he gave classes in this field at the University of Southern California while simultaneously pursuing his interest in natural history.

As well as studying the local flora, Davidson was also a keen entomologist and published many contributions to that field in western North America. After an extended stay in Clifton, Arizona, he published the first floristic account for that state and in 1923 collaborated with George L. Moxley to produce a flora of southern California. Davidson was particularly interested in the weeds of the Los Angeles area and published works such as "Changes in our weeds" (1907). Particularly interested in the genera Mentzelia L., Allium L. and Lupinus L., he proposed many new taxonomic entities (although sometimes controversially) and published "The lupines of Los Angeles County" in 1898. Before his death (shortly after he was knocked over by a car and suffered internal injuries) Davidson donated his personal plant collection to the Los Angeles County Museum and duplicates were also spread widely, although quite thinly. Some six species names were dedicated to Davidson in recognition of his work; these include Lotus davidsonii Greene and Malvastrum davidsonii B.L. Rob.

Sources:
J. Ewan, 1934, "Anstruther Davidson: An Appreciation", Madroño, 2: 124-125
R.J. van de Hoek, 2001, " Anstruther Davidson, M.D: Naturalist, Botanist and Entomologist", Natures Peace:
http://www.naturespeace.org/davidsonanthology.htm, accessed 9 May 2011.