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UNIVERSITY OF CALIFORNIA, Berkeley, Calif. 
REVERSIONS IN BERBERIS AND SAGITTARIA. 
ROBERT G. LEAVITT. 
(Plate 19.) 
THAT single individuals should recover characters lost, or at any 
rate intermitted for generations, is certainly a highly remarkable fact, 
for which we cannot as yet very clearly account. "Thus in cattle spots 
of peculiarly colored hair sometimes appear that can be definitely 
traced to ancestors several generations removed. In horses, faint 
zebrine stripes — characters evidently of considerable antiquity — some- 
times come on the shoulders, flanks, and legs, especially in colthood. 
These and a large body of similar cases of reversion are of course 
familiar to everyone through the writings of Darwin. 
Darwin noted a peculiar instance of reversion in a species of 
Melilotus. In this genus the leaflets, in assuming the sleeping position, 
twist on their stalks, and during the night stand with surfaces vertical, 
one edge presented to the sky, the other to the earth. ‘This is the case 
with fifteen species observed by Darwin. In one instance, however, 
a deviation was noted: new shoots from some cut-down plants at first 
acted, not like Melilotus, but like Trifolium, in which genus the custom- 
ary sleep-movements are executed by the sharp upward bending of 
