SOME EXPERIMENTS OF LUTHER BURBANK.
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"On the average, perhaps about six generations fairly fix a variation, but this varies greatly, depending upon previously acquired hereditary tendencies. Bringing a species into a new environment disturbs
Leaves showing a Number of Strawberry-Raspberry Hybrids and a Cluster of the Blossoms.
its fixity. Rich soil especially gives rise to variations in growth which seem to be new, and by repetition become inherently fixed. Sometimes ancestral states are brought about by good soil; sometimes
