SALICACE^: 139 



tains, and the Arctic and sub- Arctic regions of the northern hemisphere, ranging south 

 in the New World, with a few species, through the West Indies and Central America to 

 Brazil, and the Andes of Chili, and in the Old World to Madagascar, southern Africa, 

 the Himalayas, Burmah, the Malay peninsula, Java, and Sumatra. Of the 160 or 170 species 

 which are now recognized about seventy are found in North America. Of these twenty- 

 four attain the size and habit of trees, the others being small and sometimes prostrate 

 shrubs. Of exotic species, Salix alba, L., and Salixfragilis L., important European timber- 

 trees, are now generally naturalized in the northeastern states. The flexible tough branches 

 of several species are used in making baskets; the bark is rich in tannic acid and is used in 

 tanning leather and yields salicin, a bitter principle valuable as a tonic. Many of the 

 species are cultivated as ornamental trees. 

 Salix is the classical name of the Willow-tree. 



CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES 



Scales of the flowers deciduous, pale straw color. 

 Stamens 3 or more. 



Leaves green on both surfaces; petioles without glands at the base of the leaves; 

 branchlets easily separable. 



Branchlets reddish or grayish purple; leaves mostly narrow-lanceolate; capsule 

 glabrous. 1. S. nigra (A, C, E). 



Branchlets yellowish-gray; leaves lanceolate to elliptic-lanceolate; capsule often 

 more or less pubescent. 2. S. Gooddingii (F, G, H). 



Leaves (at least when fully grown) pale or glaucous below. 

 Petioles without glands. 

 Branchlets easily separable. 



Leaves narrow-lanceolate to lanceolate; petioles less than ' long. 



3. S.Harbisonii(C). 

 Leaves lanceolate to ovate-lanceolate, caudate; petioles '-f ' long. 



4. S. amygdaloides (A, B). 

 Branchlets not easily separable. 



Capsules short-stalked (pedicels hardly more than ^' long), ovoid-conic, up 

 to 5' in length; leaves more or less narrow-lanceolate, petioles glabrous or 

 nearly so. 5. S. Bonplandiana (H). 



Capsules long-stalked (pedicels ri'-e' long), more or less acuminate. 

 Petioles puberulous; leaves lanceolate to ovate-lanceolate; stipules without 

 glands on their inner surface; capsules hardly more than \' long. 



6. S.laevigata (G, F). 



Petioles hairy-tomentose; leaves lanceolate; stipules glandular on their inner 

 surface; capsules \'-\' long. 7. S. longipes (C, D.) 



Petioles glandular; leaves lanceolate to broadly ovate, caudate; branchlets easily 

 separable. 

 Leaves distinctly pale or glaucous below, lanceolate to ovate-lanceolate. 



8. S. lasiandra (B, G). 



Leaves pale green below, ovate to elliptic-lanceolate, abruptly caudate-acu- 

 minate. 9. S. lucida (A). 

 Stamens 2. 



Stigmas linear, 4 or 5 times longer than broad. 



Leaves linear, hardly more than \' long; anthers very small, globose; aments small, 



in fruit hardly up to *' in length. 10. S. taxifolia (H). 



Leaves linear-lanceolate to elliptic-lanceolate; up to 2' in length; anthers ellipsoid; 



aments longer 11. S. sessilifolia (B, G). 



Stigmas short, hardly 2 or 3 times longer than broad. 



