KEYS TO THE GENERA 39 



* Leaves palmately veined and lobed. (A.) 



A. Leaves slightly lobed (usually with notched border). Philad^l- 



phus (p. 196). 

 A. Leaves decidedly 3-lobed. Vibrirnum (p. 219). Acer (p. 103). 

 A. Leaves 5-11-lobed. Acer (p. 103). 



A. Some leaves 2- or 3-lobed, others merely notched, others with 

 3 blades. Forsythia (p. 274). 



* Leaves feather-veined and lobed. (B.) 



B. Leaves very large, 6 inches or more long. Hydrangea (p. 192). 

 B. Leaves 2-6 inches long, some serrate, some 3-lobed, some 3-bladed. 



Forsythia (p. 274). 

 B. Leaves under 2J inches long, some lobed, others not. Symphori- 

 cdrpos (p. 228). Syrlnga (p. 27.5). 



Key 3a. Key based on flowers. 



* Flowers conspicuous either by clusters or by large individual flowers. 



(A.) 

 A. Flowers yellow, bell-shaped, 4-lobed, in early spring. Forsythia 



(p. 274). 

 A. Flowers white to light purplish with tube and 4-lobed spreading 



border. (Persian Lilac) Syrlnga p^rsica laciniJita (p. 277). 

 A. Flowers white, small or large, or small and large in clusters, in 



spring. Vibiirnum (p. 219). 



A. Flowers pinkish white, large in elongated clusters, in summer. 

 Hydrangea (p. 192). 



* Flowers inconspicuous either in size or by dull colors. (B.) 



B. Leaves decidedly and radiately lobed ; fruit dry, 2-winged. Acer 

 (p. 103). 



B. Leaves slightly lobed ; fruit 2-seeded berries. Symphoricarpos 

 (p. 228). 



Key 3b. Key based on fruit. 



* Fruit fleshy, small (or absent). (A.) 



A. Drupes red or black with flattened stones (or without fruit, all 

 flowers sterile). Vibiirnum (p. 219). 



A. Berries white or red with 2 seeds. Symphoricarpos (p. 228). 

 •Fruit dry. (B.) 



B. Fruit 2-winged, 2-seeded. Acer (p. 103). 



B. Fniit elongated, 2-celled, 4-seeded. (Lilac) Syrfnga (p. 275). 

 B. Fruit many-seeded. Forsythia (p. 274). Hydrangea (p. 192). 

 Philad^lphus (p. 196). 



Key 4. Leaves opposite, compound. 

 Key based mainly on leaves and fruit. 



