This paper explores the efforts of two Berkeley geneticists E. B. Babcock and G. Ledyard Stebbins to understand the genetic basis of evolutionary change in the complex plant genus, Crepis. The paper introduces us to an important research project that has been neglected by historians. Begun in the nineteen-teens, the project on the genetics and systematics of the genus Crepis (and its relatives) was meant to emulate the success of the Drosophila genetics research program that was orchestrated by Thomas Hunt Morgan at Columbia University and later at the California Institute of Technology. The project was in fact Babcock's dream of finding an easily tractable model organism that would integrate genetics with systematics, but that would also resolve some persistent problems in plant genetics that remained unexplained after Mendel. The paper traces the history of the articulation of the polyploid complex and ends with the publication of Babcocks' Genus Crepis in 1947. The paper additionally locates Babcock and Stebbins in the agricultural context of the University of California, Berkeley, and Babcock's pioneering efforts to create one of the first departments of genetics in the United States.

Key words: Berkeley, Crepis, E. B. Babcock, G. L. Stebbins, Mendelian genetics