WG Sumner and Minority College Admissions

In Muccigrosso, _A Basic History of Conservatism_, the author claimed that WG Sumner favored admitting women and minorities to Yale University, where he taught sociology and other subjects.

I am trying to track down primary sources to that effect. Most secondary literature attributes the racism of the era to Sumner because of his philosophy that stateways cannot easily change "folkways." This is a caricature of the man's views, of course, so all the more important to explore his views on race.

In"Conquest of the United States by Spain," he makes several references to the barbaric treatment of blacks, Indians, Chinese and what could the Filipinos expect, he asked, based on our record at home?

http://praxeology.net/WGS-CUS.htm