VIII. 2. THE HEART-LEAVED WILLOW. 275 



sometimes toothed, and pointed above and below, or serrate. 

 The leaves, when young, are downy on both surfaces. 



This willow seems to be nearly allied to S. tristis, through 

 the variety called by Pursh & recurvdta ; and connects them 

 with S. conifcra. Had it not been for the high authority of Dr. 

 Barratt, I should have associated this with the cinereous group. 



Group Eighth. The Cordate Willows. Cordata. Barratt. 



Aments slightly stalked, ovate, cylindrical, expanding with 

 the leaves. Scales subciliate, red or yellowish. Stamens two or 

 three. Ovaries stalked, smooth. Leaves cordate, or attenuate 

 at base, smooth. Stipules half -heart-shaped, serrate. Tall shrubs 

 with dichotomous, flexible, smooth branches. — Barratt. 



" The aments in this section are invested with a double cov- 

 ering: the outer being a hard scale or shield; the inner, a thin 

 membranous envelope. This last is generally ruptured trans- 

 versely, and is elevated like a cap or calyptra on the summit of 

 the expanding anient. This membrane is sometimes found ad- 

 hering to the inner surface of the hard scale or shield. It is 

 most perfectly formed in S. Torreydna, and next in S. corddta. 

 Both these species of willow begin to expand their filaments at 

 the apex of the aments. The floral leaves (four or five) are 

 from half to three quarters of an inch long. The fertile aments 

 of & rigida, the largest of this section, when ripe, form a densely 

 fruited raceme three to four inches long. The mature germens 

 are sub-rhomboidal at the base, and somewhat flattened, vary- 

 ing in color from green to a reddish brown." — Barratt. 



Sp. 19. The Heart-leaved Willow. & corddta. Willdenow. 



Leaf figured in Annals of Botany, II, Plate V, fig. 3. 



Leaves oblong, lanceolate, acuminate, heart-shaped, rarely acute at base, 

 sharply serrate, smooth, paler beneath ; stipules large, ovate-roundish, cartila- 

 ginous-serrate ; aments expanding with the leaves ; stamens about three ; scales 

 lanceolate, woolly, black ; ovaries stalked, lanceolate, smooth ; style very short; 

 stigmas cleft. — Hooker, Fl. Bor. Am., II, 149. Pursh, II, 615. Willdenow, 

 IV, 666. Muhlenberg, Ann. Bot., II, 64. 



This is a beautiful low tree, varying from eight or ten. to 

 twelve or fifteen, and even twenty or more feet in height. 



