98 BOTANICAL GAZETTE [Aucust 
face of the hypocotyl outgrowths which develop into new shoots. 
These shoots also arise from mature cells which in the normal course 
of events remain as permanent tissue. Nor is this power of organ- 
izing new shoot primordia confined to the stems and roots, but is 
also possessed by many leaves, as in the well known cases of Begonia, 
. Bryophyllum, Cardamine pratensis, Tol- 
miea Menziesii, and many other plants 
roots. In a few cases, as in Salix, there 
may exist on the stem primordia already 
organized, but in the great majority of 
of the stem of Salix be cut out from the 
rest and kept moist, there will appear 0 
it both roots and shoots, each arising, 
however, from buds already laid down. 
In the axils of the leaves of many annué® 
shoots are very minute bud primordia, 
which normally do not develop. If the 
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(fig. 1). Many stems, probably the 
majority, if removed from the root sy _ 
tem and kept moist will produce new 
stems these are not present. If a portion 
Fic. x top of the plant be cut off, these at on 
form new shoots. In our trees 
shrubs the buds formed in the leaf axils do not develop until o : 
following year; but if at any time during the spring the tip fe 
young shoot be removed, a number of these buds, usually those neal 
the top, at once develop shoots. | : 
We have in these cases at least three seemingly diverse phenomeni: 
(x) the part removed is entirely restored by the growth of the cells 
immediately at the cut surface; (2) there is no growth of embryomt 
tissue at the wounded surface, but at a greater or less distance pes 
It the organization of entirely new primordia which develop organs 
that replace those removed; (3) the organ removed, e. g., the § . 
1s restored by the development of already existing dormant buds 
Between these no hard and fast lines can be drawn, for they all exhibit 
intergradations, and between the third case—the development ‘ 
latent buds—and normal vegetative growth no sharp separation 
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