London, Toronto, and New York: J.M. Dent and E.P. Dutton & Co. 1920.
Hardcover. Near Fine in a Good dust jacket. First edition, American issue. Volume I: xvi, 244 pp; Volume II: ix, 240 pp, with index and 22 color plates. Lightly bumped corners; else fine. Dust jackets chipped at spine ends and have internal reparis with archival tape. Now in mylar covers. The subject matter covered here first appeared in Hudson's Argentine Ornithology, published in 1888-89, but here he has eliminated some details pertaining to taxonomy. Hudson notes in the introduction that "about a quarter of the entire number of South American species [of birds] inhabit Argentina, and about half that number inhabit the Plata district....The species known to me personally number 233, but many more have been added since I left the country."