Zoologist who collected mainly birds and some plants in Central America for Godman and Salvin's Biologia Centrali-Americana (1888). Born in Monroe, Indiana, Gaumer spent part of his youth in Kansas where he entered university in 1868. He graduated in 1876 and later took his master's degree in 1893. Prior to this he travelled in Cuba (1878), Yucatán (1878-1881) and the south-west U.S. (1881-1884), chiefly making ornithological collections. From 1882-1884 he was professor of natural sciences at the University of North Mexico. It was around this time that his sons were born in Arizona, where Gaumer then resided with his wife, Virdilla (née McGee). In 1884 he moved permanently to Yucatán, where he practised medicine in Izamal. His later collections, sometimes made with his sons George and John, were mainly botanical. Plant species named in his honour include the rare cactus Mammillaria gaumeri Orcutt. The rodent Gaumer's Spiny Pocket Mouse (Heteromys gaumeri J.A. Allen & Chapman), found in the Yucatán, is also named after him.

Sources:
J.H. Barnhart, 1965, Biographical Notes Upon Botanists, 2: 36
W.B. Hemsley, in F.D. Godman and O. Salvin (editors), 1888, Biologia Centrali-Americana, 4: 137.