=A.= Rather small Willows, 10 to 30 ft. high, with broad leaves, usually not over twice as long as wide; cultivated. (=B.=) =B.= Leaves glossy dark green on the upper side, taper-pointed 7. =B.= Leaves with white cottony hairs beneath 10. =B.= Leaves rough-veiny beneath 13. =A.= Rather large Willows, 12 to 80 ft. high, with the bark of the trunk very rough; leaves more elongated. (=C.=) =C.= Petioles of the leaves not glandular; tree 10 to 40 ft. high. (=D.=) =D.= Leaves green on both sides when mature 1. =D.= Leaves glaucous beneath 2. =C.= Petioles of the leaves usually glandular; tree 50 to 80 ft. high. (=E.=) =E.= Young leaves green above and glaucous beneath 3. =E.= Young leaves ashy gray or silvery white on both sides 4. =A.= Small trees or almost shrubs, under 18 ft. high; bark of trunk rather smooth. (=F.=) =F.= Leaves ovate rather than lanceolate, sometimes truncate or even cordate at base. (=G.=) =G.= Leaves quite broad, shining on both sides. (=H.=) =H.= Leaves bright green; twigs polished green 6. =H.= Leaves very dark green, strongly fragrant when bruised 7. =G.= Leaves pale-downy beneath, often cordate at base 8. =F.= Leaves usually wider near the acute or acuminate tip, glaucous beneath. (=I.=) =I.= Branches very twiggy; leaves often opposite; twigs olive-color or reddish 9. =I.= Branches not very twiggy; leaves all alternate 11, 12. =F.= Leaves very long and slender, almost linear 14. [Illustration: S. nìgra] 1. =Sàlix nìgra=, Marsh. (BLACK WILLOW.) Leaves narrowly lanceolate, tapering at the ends, serrate, smooth except on the petiole and midrib, green on both sides; stipules small (large in var. _falcata_), dentate, dropping early. Branches very brittle at base. A small tree, 15 to 35 ft. high, with rough black bark. Common along streams, southward, but rare in the northern range of States. [Illustration: S. amygdaloìdes.] 2. =Sàlix amygdaloìdes=, Anderson. (WESTERN BLACK WILLOW.) Leaves 2 to 4 in. long, lanceolate or ovate-lanceolate, attenuate-cuspidate, pale or glaucous beneath, with long slender petioles; stipules minute and soon falling. A small tree, 10 to 40 ft. high, from central New York westward. It is the common Black Willow of the streams of Ohio to Missouri. [Illustration: S. frágilis.]