Fisk Holbrook Day (1826-1903) was a physician and an amateur geologist in Wisconsin who developed an impressive collection of Silurian-age fossils. The collection is now at Harvard University.[1]
Day was born on March 11, 1826, in Richmond, New York. He graduated from Jefferson Medical College in Philadelphia, Pennsylvania, in 1849. He moved to Wauwatosa, Wisconsin, and lived there for 40 years, "and at one time was considered its most prominent citizen." He became the first physician to serve as Superintendent of the Milwaukee County hospital and led in many reforms for the hospital and for a system of county insane asylums throughout Wisconsin.[1]
He once could sell a trilobite for "the then-extravagant sum of $100".[1] The fossil trilobite was named Bumastus dayi in honor of Day.[2][3]