LEGUMINOS.E 



597 



CONSPECTUS OF THE NORTH AMERICAN SPECIES. 



Peduncles bibracteolate at apex; stipules becoming spinescent. 



Leaves 10-14-pinnate; pinnae with 15-30 pairs of leaflets; blade of the bract of the flower 



produced into a short point. 1. L. Greggii (E). 



Leaves 2-4-pinnate; pinnae with 4-8 pairs of leaflets; blade of the bract of the flower 



produced into a long slender villose tip. 2. L. retusa (E). 



Peduncles without bracts; stipules minute, caducous; leaves 30-36-pinnate; pinnae with 



30-60 pairs of leaflets. 3. L. pulverulenta (E). 



1. Leucaena Greggii S. Wats. 



Leaves 6 '-7' long and broad, with a slender rachis furnished on the upper side with a 

 single elongated bottle-shaped gland between the stalks of each pair of pinnae; pinnae 10-14, 

 remote, short-stalked, with 15-30 pairs of leaflets; stipules gradually narrowed into a long 

 slender point, becoming rigid and spinescent, ' to nearly \' long and persistent for two 

 or three years; leaflets lanceolate, acute or acuminate, often somewhat falcate, nearly 

 sessile or short-petiolulate, full and rounded toward the base on the lower margin, nearly 

 straight on the upper margin, gray-green, ultimately nearly glabrous, \'-\' long, about \' 

 wide, with a narrow midvein and obscure lateral nerves. Flowers on slender pedicels, 

 in heads f'-l' in diameter, on stout peduncles 2'-3' long furnished at apex with 2 irreg- 

 ularly 3-lobed bracts, and solitary or in pairs; calyx coated with hairs only near the apex, 

 much shorter than the spatulate glabrous more or less boat-shaped petals; ovary villose 

 with a few short scattered hairs. Fruit 6'-8' long, \ -f ' wide, narrowed below into a 

 short stout stipe, acuminate and crowned at apex with the thickened style, 3' f' long, 





cinereo-pubescent until nearly fully grown, becoming nearly glabrous at maturity, much 

 compressed, with narrow wing-like margins; seeds conspicuously notched by the hilum, 

 f ' long and \' wide. 



A tree, 15-20 high, with a stem 4 '-5' in diameter, and stout zigzag red-brown branch- 

 lets marked by numerous pale lenticels, coated at first with short spreading lustrous 

 yellow deciduous hairs found also on the young petioles and lower surface of the unfolding 

 leaflets, the peduncles of the flower-heads and their bracts. Bark about f ' thick, dark 

 brown, divided into low ridges and broken on the surface into small closely appressed 

 persistent scales. Wood heavy, hard, close-grained, rich brown streaked with red, with 

 thin clear sap wood. 



Distribution. Mountain ravines and the steep banks of streams; western Texas from the 

 valley of the upper San Saba River to that of Devil's River; and southward into Mexico. 



