American Horticultural Society, October 1952, pg. 237-259; Concerning Rex Begonia, by B. Y. Morrison The following descriptions are recorded from observation notes made of the living collection during 1951-1952: Bertha Boner. Medium sized leaves, with moderate spiral curl, ruffled margins. Central area and margin dark green almost completely covered with smallish silver dots. The zone of silver-green, solid and tending to run out into the major serrations.
