XIX. Salicaceae. Willow Family

Trees or shrubs, the wood soft and light, bark bitter; leaves alternate undivided; flowers of both kinds in catkins, one to each bract, without perianth; fruit a pod bearing numerous seeds furnished with long silky down.

I. Salix. (Tourn.) L.

1. S. Candida. Flugge. Hoary Willow.

2. S. Barclayi. Anders. Barclay's Willow.

3. S. Barrattiana. Barratt's Willow.

4. S. Bebbiana. Sargent. Brown Willow.

5. S. nivalis. Hook. Alpine Willow.

6. S. petrophila. Rydb. Dwarf Willow.

7. S. vestita. Pursh. Hairy Willow.

8. S. sitchensis. Sanson. Sitka Willow.

9. S. arctica. Pall. Arctic Willow. II. Populus. (Tourn.) L.

1. P. tremuloides. Michx. Aspen Poplar.

2. P. balsamifera. L. Balm of Gilead.

3. P. trichoearpa. Hook. Western Balsam Poplar.

4. P. acuminata. Rydb. Cottonwood.