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cies show marked sexual variations in the buds and _ branches. 
The staminate plants generally have larger and stouter buds and 
coarser branches. No willow that has come to our attention pre- 
sents so conspicuous sexual variation as S.cordata. The variation 
relates not only to the size of the bud, but also to the form. 
It is highly desirable to prove experimentally that hybridiza- 
tion may take place between these willows, and that as an effect 
of such hybridization individuals will be produced like our forms. 
These experiments we propose to undertake. It does not seem 
desirable to await the result, since European willows, as well as 
American, are inclined to hybridize freely beyond a doubt, and 
our observations published may encourage others to report ob- 
servations upon similar forms. 
A detziled description may assist in identifying these forms 
when found in other places. 
Salix candida Fliigge x S. petiolaris Smith. 
Catkins, at anthesis, 2 cm. long, at the time of dehiscence of 
capsule 4—5 cm., upon slender pedicels which bear two or three 
foliaceous bracts. The bracts not enlarging as the capsules mature. 
Catkins rather closely flowered at anthesis, moderately loosely 
flowered at maturity. Capsules, at anthesis, elliptic-lanceolate, 14 
mm. long, style I mm., smooth and purple, capsule densely white 
tomentose, stigmas conspicuously two branched, the apices of the 
branches two lobed. Pedicels 1% mm., about equalled by the 
slightly clavate gland, surpassed by the black scales; at maturity 
lanceolate, 6-7 mm. long and creamy whitish and tomentose, 
pedicels not longer than at anthesis, the looser character of the 
catkin being due to the elongation of the main axis. 
Leaves narrowly elliptical, tapering very gradually to an acute 
base and apex, obscurely toothed and scarcely revolute, smooth 
and light green above, finely tomentose and very white and veiny 
beneath, petioles 1 cm. long, twice the length of small lance-subu- 
late, revolute stipules. Young leaves showing a decided tendency 
to blackening in drying. 
A shrub two or three feet high diffusely spreading, the young 
part of the shoots pruinose tomentose, becoming, in age, brown 
and polished. Buds ovate oblong, blunt, slightly So bud | 
scales chestnut or darker, nearly smooth. : 
