Marcellus Graeme Boss (January 21, 1901 – March 21, 1967) was an interim Governor of Guam from November 14, 1959, until his resignation on August 22, 1960.

[1] Boss first entered Guamanian administration with a 1957 appointment by President Dwight D. Eisenhower to the post of Secretary of Guam.

[2] He also served as a Republican member of the Kansas State Senate[3] prior to becoming involved in the government of Guam.

[2] He was city clerk and city attorney of Kiowa, Kansas,[4] and had a thirty-year law career in Columbus, Kansas.

[5] He died of a heart attack on March 21, 1967, and was buried at the City Cemetery in Columbus, Kansas.