SALICACEAE. 93 



IV. CORDATAE. 



Capsule long-stipitate ; stipe in fruit 1.5-6 mm. long, equalling or longer than 



the bracts ; style 0.5 mm. or less long ; aments leafy-peduncled. 

 Leaves dark green above, strongly serrate ; young branches not light yellow. 



10. 5". cordata. 

 Leaves yellowish green, entire or crenulate ; young branches light yellow. 



11. S. Watsoni. 

 Capsule subsessile or very short-stipitate ; stipe in fruit less than 1.5 mm. long 



and much shorter than the bracts; style 0.5-1.5 mm. long; aments subsessile 

 and naked or subtended by a few small leaves. 

 Branches without a bloom. 



Leaves lanceolate to ovate or obovate, more or less distinctly serrate. 

 Leaves thin, ovate or obovate, light green and dull above. 



12. S. padophylla. 

 Leaves firm, dark-green and shining above, lanceolate. 



Style 1.5 mm. long; aments 2.5-6 cm. long. 13. 5". pseudocordata. 

 Style less than i mm. long ; aments 1-2.5 cm. long. 



14. 5". monticola. 



Leaves linear-lanceolate to oblong, entire. 15. S. Wolfii. 



Branches with a bloom. 16. S. irrorata. 



V. ROSTRATAE. 



Leaves linear to lanceolate or oblanceolate. 



Leaves more or less silky; branches usually with a bloom. 



17. 5*. Geyeriana. 



Leaves not silky; branches without a bloom. 18. 5". macrocarpa. 



Leaves ovate to obovate. 



Mature leaves thin, glabrous, faintly nerved. 19. 5". perrostrata. 



Mature leaves firm, pubescent or tomentose beneath, more strongly nerved. 



20. S. Bebbiana. 

 VI. BRACHYSTACHYAE. 

 Only represented by 21. S. Nuttallii. 



s . VII. PELLITAE. 



Only represented by 22. 5". pachnophora. 



VIII. ARCTICAE. 



Leaves grayish-villous on both sides, although less so above. 



Twigs white-villous ; branches yellow or grayish. 23. S. brachycarpa. 

 Twigs puberulent, rarely villous ; branches usually purplish. 



Leaf-blades oblong or linear-oblong ; bracts obovate ; shrub depressed. 



24. S. pseudolapponum. 

 Leaf-blades oblanceolate or obovate-oblanceolate ; bracts oblong ; shrub not 



depressed. 25. S. glaucops. 



Leaves glabrate or when young covered with white hairs parallel to the mid- 

 rib. 



Shrubs not creeping ; leaf-blades oval to oblong or lanceolate. 

 Aments leafy-peduncled. 25. S. glaucops glabrata. 



Aments subsessile, naked from lateral buds. 26. 5". chlorophylla. 



Shrubs creeping; leaf-blades obovate to oblanceolate. 



27. 5". petrophila. 



IX. RETICULATAE. 

 Only represented by 28. 5". saximontana. 



1. Salix Wrightii Anders. Along streams from Tex. to Colo, and Calif. 

 Alt. 4000-5500 ft. Arkansas River; Denver. 



2. Salix amygdaloides Anders. Along streams from Que. to Wash., N. Y., 

 Mo. and Ariz. Alt. 4000-7000 ft. Plains, Colorado Springs; Denver; Wai- 



