Leon Frank Czolgosz (Polish: "Czołgosz" ; May 5, 1873 – October 29, 1901) was an American anarchist and former steel worker who assassinated U.S. President William McKinley in September 1901.
 Czolgosz was executed just over seven weeks later.
Edward Anthony Spitzka (June 17, 1876 – September 4, 1922) was an American anatomist who autopsied (29 Oct 1901) the brain of Leon Czolgosz, the assassin of president William McKinley.
 (In 1881, his father Edward Charles Spitzka, a famous neurologist and medical specialist in mental diseases, testified to the insanity of Charles Guiteau, the assassin of President James A. Garfield, at Guiteau's murder trial.)
Murray Bookchin (January 14, 1921 – July 30, 2006) was an American anarchist and libertarian socialist author, orator, historian, and political theorist.
 A pioneer in the ecology movement, Bookchin initiated the critical theory of social ecology within anarchist, libertarian socialist, and ecological thought.
 He was the author of two dozen books covering topics in politics, philosophy, history, urban affairs, and ecology.
 Among the most important were "Our Synthetic Environment" (1962), "Post-Scarcity Anarchism" (1971) and "The Ecology of Freedom" (1982).
 In the late 1990s he became disenchanted with the increasingly apolitical lifestylism of the contemporary anarchist movement, stopped referring to himself as an anarchist, and founded his own libertarian socialist ideology called Communalism.
Josiah Warren ( ; 1798 – April 14, 1874) was an individualist anarchist, inventor, musician, and author in the United States.
 He is regarded by some as the first American anarchist, (though he never used the term himself) and the four-page weekly paper he edited during 1833, "The Peaceful Revolutionist", the first anarchist periodical published, an enterprise for which he built his own printing press, cast his own type, and made his own printing plates.
Edward Charles Spitzka (November 10, 1852 – January 13, 1914) was an eminent late-19th century alienist, neurologist, and anatomist.
 Dr. Spitzka was the author of the landmark psychiatric manual ""Treatise on Insanity, Its Classification, Diagnosis and Treatment"" published in 1883.
 He pioneered studies of the anatomy of the human nervous system, and discovered the interoptic lobes of saurians in the human brain.
Charles Bufe, better known as Chaz Bufe, is a contemporary American anarchist author.
 Bufe primarily writes on the problems faced by the modern anarchist movement (as in his pamphlet "Listen, Anarchist!
"), and also on atheism, music theory and intentional community.
The American Anthropometric Society was an association for acquiring and storing brains of eminent persons for the purpose of research.
 The society was founded in 1889 in Philadelphia.
 Edward Anthony Spitzka, M.D., professor of anatomy at Jefferson Medical College, presented a paper on March 16, 1906 about his study of six brains bequeathed to the society.
Chuck W. Morse (born 1969) is an American anarchist, academic, translator, editor, and writer.
 He founded the Institute for Anarchist Studies and "The New Formulation: An Anti-Authoritarian Review of Books".
 Morse was the editor of "Perspectives on Anarchist Theory" and taught at the Institute for Social Ecology.
Especifismo (] , "specifism") is one of the two main forms of anarchist activism championed by FARJ (Federação Anarquista do Rio de Janeiro) and other South American anarchist organizations, the other being social insertion.
 Especifismo emerged as a result of anarchist experiences in South America over the last half of the 20th century starting with the Federación Anarquista Uruguaya (FAU), which was founded in 1956 by anarchists who saw the need for an organization which was specifically anarchist.
Edward Anthony (January 31, 1819 – December 14, 1888) was an American photographer and one of the founders of E. & H. T. Anthony & Company which was the largest manufacturer and distributor of photographic supplies in the United States during the 19th century.
 Edward Anthony was a brother of Henry T. Anthony and had a very close business relationship with Mathew Brady.

Question: Edward Anthony Spitzka autopsied the brain of the American anarchist who assassinated which President?
Answer: William McKinley