sippi and Ohio
basins to Arkansas, Indiana, and Illinois.

=Habit.=--A slender, medium-sized tree, attaining a height of 30-50
feet, reaching farther south a maximum of 90 feet; trunk 9-18 inches in
diameter, usually branching high up, forming a rather open hemispherical
or narrow-oblong head; branches irregular, short, rising, except the
lower, at a sharp angle; branchlets stout, roundish, varying in color,
degree of pubescence, and glossiness, becoming rough after the first
year with the raised leaf-scars; spray sparse.

=Bark.=--Bark of trunk dark ash-gray, very rough, and broken into
loosely attached narrow plates in old trees; in young trees light
ash-gray, smooth at first, becoming in a few years roughish, low-ridged.

=Winter Buds and Leaves.=--Buds conical, acute, more or less resinous.
Leaves 3-6 inches long, two-thirds as wide, densely white-tomentose when
young, at length dark green on the upper side, lighter beneath and
smooth except along the veins; outline ovate, wavy-toothed; base
heart-shaped, lobes often overlapping; apex obtuse; leafstalk long,
round, downy; stipules soon falling.

=Inflorescence.=--April to May. Sterile catkins when expanded 3-4 inches
long, at length pendent; scales cut into irregular divisions, reddish;
stamens numerous, anthers oblong, dark red: fertile catkins spreading,
few and loosely flowered, gradually elongating; scales reddish-brown;
ovary short-stalked; styles 2-3, united at the base; stigmas 2-3,
conspicuous.

=Fruit.=--Fruiting catkins spreading or drooping, 4-5 inches long:
capsules usually erect, ovoid, acute, shorter than or equaling the
slender pedicels: seeds numerous, white-hairy.

=Horticultural Value.=--Not procurable in New England nurseries or from
collectors; its usefulness in landscape gardening not definitely known.

[Illustration: PLATE XVI.--Populus heterophylla.]

1. Winter buds.
2. Branch with sterile catkin.
3. Sterile flower.
4. Scale of sterile flower.
5. Branch with fertile catkin.
6. Fertile flower.
7. Fruiting branch with mature leaves.

=Populus deltoides, Marsh.=

_Populus monilifera, Ait._

COTTONWOOD. POPLAR.

=Habitat and Range.=--In moist soil; river banks and basins, shores of
lakes, not uncommon in drier locations.

Throughout Quebec and Ontario to the base of the Rocky mountains.

Maine,--not reported; New Hampshire,--restricted to the immediate
vicinity of the Connecticut river, disappearing n