598 



TREES OF NORTH AMERICA 



2. Leucaena retusa Benth. 



Leaves 3' or 4' long and 4' or 5' wide, with a slender petiole and rachis and 2-4 pairs of 

 pinnae 6'-10' long, remote, long-stalked, with 4-8 pairs of short-stalked leaflets furnished be- 

 tween their stems with a single globose white gland found also occasionally on the upper side 

 of the rachis between the stems of the pinnae; stipules ovate, gradually narrowed into a long 

 slender tip, \' in length, often persistent through the season; leaflets obliquely obovate 

 or elliptic, rounded and apiculate at apex, obliquely rounded or cuneate at the unsym- 

 metric base, entire, short-petiolulate, villose-pubescent like the rachis and petiole when 

 they first appear, soon glabrous, and at maturity thin, blue-green, -'-!' long and \'-\' 

 wide, with a slender midrib, and prominent veins extending obliquely toward the apex 

 of the leaflet, those of the lowest pair more prominent and starting from near its base. 



Fig. 548 



Flowers short-stalked in the axil of a peltate bract, its blade produced into a long slender 

 villose tip, appearing continuously from April until October in dense globose heads f ' in 

 diameter, on villose bibracteolate axillary, single or fascicled peduncles l|'-3' in length; 

 calyx thin, tubular, 5-toothed at apex; petals narrow-oblong, hardly longer than the calyx: 

 stamens 10, shorter than the bract of the flower; anthers glabrous. Fruit solitary or 

 clustered, on a puberulous peduncle 3'-5' in length, 6'-10' long, Y~ wide, gradually 

 narrowed below into a stout stipe, the acuminate apex terminating in the thickened per- 

 sistent style, glabrous and dark reddish brown; seeds |' long and | 7 wide. 



A tree, occasionally 25 high, with a trunk 6'-8' in diameter, and slender branchlets 

 pubescent when they first appear, becoming puberulous and orange-brown or reddish 

 brown at the end of their first season; more often a shrub. 



Distribution. Texas; steep rocky hillsides, and on the summits of limestone bluffs; 

 (Uvalde, Valverde, Kemble, Real and Jeff Davis Counties). 



3. Leucaena pulverulenta Benth. Mimosa. 



Leaves 4'-7' long and 3'-4' wide, with a slender petiole usually marked by a large 

 dark oblong gland between the somewhat enlarged base and the lowest pair of the 

 30-36 nearly sessile crowded pinnae, each with 30-60 pairs of leaflets, and minute cadu- 

 cous stipules, when they unfold covered like the peduncles and flower-buds with dense 

 hoary tomentum, and at maturity puberulous on the petiole and rachis; leaflets linear, 

 acute, rather oblique at base by the greater development of the upper side, sessile or very 



