542 



TREES OF NORTH AMERICA 



seeds ovate, thick, flattened on the inner surface by mutual pressure, \' long, sus- 

 pended transversely in 2 ranks on short straight funicles, light brown, lustrous, and 

 faintly marked by large oval rings. 



A tree, 20-30 high, with a straight trunk 12'-18' in diameter, separating 6-8 

 from the ground into numerous long pendulous branches forming a wide round 

 spreading head, and slender terete or slightly striate angled branchlets, glabrous or 

 at first puberulous, and armed with straight rigid terete spines developed from the 

 persistent stipules and sometimes 1^' long. Bark of the trunk thin, reddish brown, 

 irregularly broken by long reticulated ridges, exfoliating in large thin scales. Wood 

 heavy, hard, close-grained, rich reddish brown, with thin pale sapwood; in India 

 used for the knees of small vessels and in agricultural implements. 



Distribution. Now widely spread by cultivation through the tropical and sub- 

 tropical regions of the two worlds and probably a native of America from western 

 Texas to northern Chili; growing in Texas apparently naturally in the arid and 

 almost uninhabited region between the Nueces and Rio Grande. 



Largely cultivated in southern Europe for its fragrant flowers used in the manu- 

 facture of perfumery, as an ornament of gardens in all warm countries, and in India 

 as a hedge plant. 



2. Acacia tortuosa, Willd. 



Leaves generally less than V long, short-petiolate, with slender puberulous rachises 

 and usually 3 or 4 pairs of pinnae, early deciduous; pinnae sessile or short-stalked, 

 remote, with 10-15 pairs of linear somewhat falcate leaflets, acute, tipped with 

 minute points, subsessile, light green, glabrous, ^j/ jV long. Flowers minute, 

 bright yellow, very fragrant, in the axils of clavate pilose bractlets, in heads \'-\' in 

 diameter, appearing in March with or just before the unfolding leaves, on clustered 

 or solitary slender puberulous peduncles, \'-$' long, and furnished at the apex with 

 2 minute connate bracts; calyx only about one third as long as the corolla, with short 



puberulous lobes; corolla puberulous at the apex, less than one half as long as 

 the filaments; ovary covered with short close pubescence. Fruit elongated, linear, 

 slightly compressed, somewhat constricted between the seeds, 3'-5' long, about \' 

 wide, dark red-brown and cinereo-pub.erulous; seeds in 1 series, obovate, com- 

 pressed, dark red-brown, lustrous, about ^' long, faintly marked by large oval rings. 



