In the 1888 catalog that there was a psychology class offered to juniors and seniors. The prior catalog, 1874, listed no such class. According to the 1942-1943 College Catalog philosophy and psychology were one department under Professor James Wilkinson Miller. The next catalog in the University Archives is for 1944-1945 when psychology and philosophy are separate departments. Professor Miller is still the head of philosophy, while Professor Edgar Maria Foltin was the head of psychology.
Information about the current department is available at http://www.wm.edu/psychology/. Further information about this individual or organization may be available in the Special Collections Research Center Wiki: http://scrc.swem.wm.edu/wiki/index.php/Dept. of Psychology.