Key to the Genera xxv 



I. LEAVES OPPOSITE, COMPOUND, AND DECIDUOUS 



1 . Leaves palmately compound ; fruit a capsule . AESCULUS, p. 308. 



1 . Leaves pinnately compound or 3-foliate 2 



2. Leaflets entire or finely toothed; fruit a samara 



FRAXINUS, p. 342. 



2. Leaflets deeply and sharply toothed 3 



3. Flowers yellow, showy; fruit a linear capsule 4-8 inches long; 

 southwestern TECOMA, p. 363. 



3. Flowers small; fruit a double samara or drupe 4 



4. Fruit a double samara in racemes; terminal bud present with 

 one pair of outer scales ACER NEGUNDO, p. 307. 



4, Fruit a small drupe in dense clusters; terminal bud absent, 

 lateral scaly SAMBUCUS, p. 365. 



II. LEAVES OPPOSITE AND SIMPLE 



1. Leaves persistent, entire, thick; fruit a drupe; southeastern 

 coastal plain OSMANTHUS, p. 357. 



1. Leaves deciduous, not leathery * 2 



2. Leaves palmately lobed; fruit a double samara. ACER, p. 294. 

 2. Leaves not lobed, fruit not a double samara 3 



3. Leaves entire 4 



3. Leaves toothed 10 



4. Leaves heart-shaped, 5-12 inches long 5 



4. Leaves linear to ovate, less than 5 inches long 6 



5. Leaves 6-20 inches long, densely hairy below; flowers purple; 

 capsule leathery, ovoid, 1-2 inches long. . PAULOWNIA, p. 361. 



5. Leaves 8-12 inches long, slightly hairy below; flowers white; 

 capsule linear, 8-20 inches long CATALPA, p. 361. 



6. Leaves linear to lanceolate; fruit a linear capsule 7-12 inches 

 long; southwestern CHILOPSIS, p. 359. 



6. Leaves suborbicular to elliptic 7 



7. Stipules present and persistent; terminal bud absent, lateral 



minute; fruit a head of nutlike capsules 



CEPHALANTHUS, p. 363. 



7. Stipules absent; terminal bud present; fruit not a capsule 8 



8. Fruit a samara with terminal wing; southwestern 



FRAXINUS ANOMALA, p. 345. 



8. Fruit a drupe 9 



9. Leaves with arcuate venation; flowers small in heads; leaf scars 

 with 3 bundle traces CORNUS, p. 331. 



9. Leaves with pinnate venation; flowers white in panicles; leaf 

 scar with single bundle trace CHIONANTHUS, p. 357. 



10. Buds enclosed by 2 large, valvate scales; fruit a drupe; 



petioles grooved VIBURNUM, p. 367. 



1 0. Buds many-scaled ; petioles round in cross section 11 



1 1 . Leaves closely and finely serrate ; lateral buds solitary ; fruit 

 a capsule in scarlet aril EUONYMUS, p. 293. 



