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ANNE M. LUTZ 
placed and overlaps the right lateral margin of petal i, both lateral 
margins of petal I are left in (Fig. 6), and both of petal 2, out. 
Therefore the left of 2 and right of 4 are both out, and in the growing 
bud sometimes forms a sort of an X contact along the left distal 
margin of 2 and right distal of 4.^^ The right distal of 4 may grow on 
t 
Fig. 6. F2 0. gigas X 0. Lamar ckiana (de Vries), plant No. 133(1), Lafayette, 
Indiana, 1913. Detached petals of flowers showing petal cleavage resulting from re- 
versed petal arrangement at one point, the left lateral margin of petal 2 overlapping 
the right lateral of i, leaving both margins of i in, and both of 2, out, in open flower. 
Most common form of irregular arrangement and petal cleavage. a,b = right distal 
lobes; a'yb' = left distal lobes; r.m. = right lateral. margin; l.m. = left lateral mar- 
gin; l.d.m. and r.d.m. = left and right distal margins. 
1^ Since Figs. 4, 5 and 6 show flowers photographed from the stigma, instead of 
from the sepal, surface, the margins which are referred to as right and left in the 
descriptions of the bud appear in reversed positions when viewed from the inside of 
the open flowers. The margins are labeled, however, as seen from the sepal surface 
of the bud. 
