A Kelsey-Satsuma Hybrid
The Kelsey is an Oriental plum, not imported by Mr. Burbank, but used by him in hybridizing experiments. The hybrid here shown resembles the Kelsey in form, but here shows the influence of the other parent in the matter of color. It is an interesting product, but was not thought worthy of introduction.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 5 Chapter 2