34 American Midland Naturalist Monograph No. 7 



21. Leaves glabrous or more or less pubes- 

 cent, but not strigillose beneath. 

 22. Leaves minutely resinous-dotted be- 

 neath, elliptical-obovate, ciliolate; 

 flowers in axillary drooping ra- 

 cemes; corolla ellipsoid, greenish 



or pink 



Gaylussacia in 93. Ericaceae 



22. Leaves not resinous-dotted. 



23. Petioles usually 1 cm or more in 

 length ; ovary superior. 

 24. Bark spicy-aromatic ; buds 

 scaly; drupe red, 1 cm long 



at maturity 



Lindera in 74. Lauraceae 



24. Bark not aromatic; winter 

 buds naked ; drupe 6-8 mm 

 in diameter, dark purple 



when ripe 



Rhamnus in 51. Rhamnaceae 

 23. Petioles shorter; buds scaly; ovary 

 inferior; fruit a several-seeded 



berry 



Vaccinium in 93. Ericaceae 



21. Leaves strigillose and pale green beneath; 

 lateral veins running parallel to the 

 margins, the upper ones ending in the 

 apex; petals 4; sepals 4; flowers white, 

 cymose; fruit a bluish black drupe 6-8 



mm in diameter 



Cornus alternifolia in 90. Cornaceae 



Section 15. Trees and Shrubs With Alternate, .Simple, Lobcd Leaves 



1. Leaves palmately veined and lobed. 



2. Plants climbing by tendrils 52. Vitaceae 



2. Plants not climbing; tendrils none. 



3. Some of the leaves usually 3-lobcd, not serrate, aromatic 



Sassafras in 74. Lauraceae 



3. Leaves usually serrate or sinuate-dentate as well as lobed. 

 4. Trees. 



5. Leaf-lobes not serrate or sinuate; blades white-tomentose beneath 



at first; flowers and fruits in catkins ....Populus in 69. Salicaceae 

 5. Leaf-lobes serrate or sinuate-toothed. 



6. Flowers and fruits in dense, globose heads. 



7. Leaf-lobes serrate; leaves glabrous or pubescent, never white- 

 tomentose; 2-year-old branchlets often corky-ridged 



Liquidamba? in 58. Hamamelidaceae 



7. Leaf-lobes sinuate-toothed; blades white-tomentose beneath 

 when young, becoming nearly glabrous at maturity; 



branchlets terete; bark exfoliating 59. Platanaceae 



6. Staminate flowers in catkins; pistillate flowers ripening into a 

 succulent multiple fruit (a mulberry) ; leaf-lobes serrate- 

 dentate Morus in 71. Moraceae 



