Marcus Eugene Jones (April 25, 1852 – June 3, 1934) was an American geologist, mining engineer and botanist.

As an early explorer of the western United States, he is known as the authority for numerous vascular plants.

He edited and distributed several specimen series which resemble exsiccatae, among them one with the title Flora of California.

Collected by Marcus E. Jones, A. M..[1] After the death of his wife in 1915, he sold his herbarium and library to Pomona College.

[3] One of Jones' most notable accomplishments was his self-published revision of the North American species of Astragalus.