292 Small: Shrubs and Trees 



Filaments pubescent throughout : petals pubescent within : Texano- Mexican. 



Parts of the flower usually in 4's : leaflets relatively large. 



2. P. angustifolia. 



Samaras obovate. 



Leaflets with sharply serrate blades : samaras 16-19 mm. long, acute at the 

 base, the body merely glandular-dotted. 3. P. serrata. 



Leaflets with entire or merely undulate blades: samaras 8-1 1 mm. long, or 

 rarely longer, rounded or truncate at the base, the body pitted. 



4. P. niicrocarpa. 



Samaras suborbicular. 



Leaflets with entire or merely crenulate blades, the terminal one much longer 



than broad, acute or slightly acuminate. 5. P. trifoliata. 



Leaflets with crenate or crenate-lobed blades, the terminal one only slightly 



longer than broad, blunt. 

 Blades of the leaflets not lustrous : filaments nearly glabrous : anthers 



rounded or retuse at the apex. 6. P. rhombifolia . 



Blades of the leaflets lustrous above : filaments densely pubescent below : 

 anthers apiculate. 7. P. Toxicodendron. 



i. Ptelea Baldwinii T. & G. 



A shrub about 3 dm. tall, with irregularly branched stems. 

 Leaflets 3 ; blades oval or ovate, 1-2 cm. long, obtuse at both 

 ends, or the terminal one cuneate at the base, sessile, glabrous 

 except the midrib and the ciliate margins when they are young : 

 panicles few-flowered : flowers with the parts mostly in 5's: calyx 

 1.5 mm. broad: sepals oval, less than 1 mm. long, acutish, ascend- 

 ing : petals 4, oblong-oblanceolate, 4 mm. long, obtuse, undulate : 

 stamens shorter than the petals : filaments stout, hairy at the middle. 



In the vicinity of St. Johns, eastern Florida. Spring* 



2. Ptelea angustifolia Benth. 



A little known species originally described from Mexico, with 

 pubescent foliage, wholly pubescent filaments and pubescent 

 petals, is said to occur in southern and western Texas. 



3. Ptelea serrata sp. nov. 



An irregularly branched shrub, 1-2 m. tall, with glabrous 

 foliage. Leaflets 3 ; blades thinnish, oval, elliptic or elliptic-obo- 

 vate, 2.5-7 cm - l° n g> sharply acuminate, or rarely only acute, 

 rather shallowly but sharply serrate, deep green above, very pale 

 green beneath, the terminal one with a slender base : panicles 

 few-flowered: samaras obovate, 16-19 mm - long, acute at the 

 base, the wing rather delicate, the body glandular-dotted. 



On granite slopes, Stone Mountain, Georgia, Spring. 



