Cephalotaxus drupacea.

Botanical name: 

Cephalotaxus drupacea Sieb. & Zucc. Coniferae. Plum-Fruited Yew.

Japan. The female plant bears a stone-fruit closely resembling a plum in structure. The flesh is thick, juicy and remarkably sweet, with a faint suggestion of the pine in its flavor.

Sturtevant's Edible Plants of the World, 1919, was edited by U. P. Hedrick.