S8 TRIANDRIA, MOXOGYNIA. 



is aJso a single species described as African, and another 

 discovered by Loureiro in Cochinchina. The genus now 

 consists of 23 species. Most of" them produce blue flowers; 

 the North American species of a bright azure, but ex- 

 tremely evanescent. It is said that -the Japanese possess 

 a metliod of extracting the colour from the flowers of the 

 Commelina. 



39. SYENA. mild Mataca. Jluhlet. 



Calix deeply 3-parted, acute, persistent. Pe- 

 tals S, roundish. Anthers oblon.^^ 2-celled. Stig- 

 ma irifid. Capsule acuminated with the style, 

 l-cel)ed, 3-valved. 



A small sub-aquatic, repent herb, resembling moss; the 

 leaves alternate, crowded, linear, subulate, (somewhat 

 5-nerved, Aublet.); flowers solitary, axillary and re- 

 mote, the peduncle bending downwards after flowering, 

 (pedicell bibracteate, Aubl.) In the Syena, as it appears 

 in the United Slates, ihe stem is bi-fistulous (for floating) 

 as in the Calitriche^ the leaves each with a single nerve; 

 the peduncles without bractes, but furnished at the base 

 with a single valved scariose spatha; filament and an- 

 ther united, the latter shortly obovate, 2-celled, emitting 

 the pollen by 2 terminal oblique pores; style simple; stig- 

 rna entire, persistent; capsule oblong-ovate, 1-celled, 3- 

 valved; seeds 9, attached by 3s to the centre of eachk 

 valve, spherical, acute at one of the ends, longitudinally 

 traversed by elevated scabrous lines, of a hard and brit- 

 tle consistence, and a dark brown colour. 



This IS probably distinct from Aublet's plant. Existing 

 as far to the North as Virginia. 



40. LEPTANTHUS. Michaux. 



Spatha 1 to 4-flowerod. Corolla^ tube long 

 and slender; border 6-parted. Stamina seat- 

 ed upon the segments of the corolla. Anthers 

 linear, or of 2 different forms, the other trian- 

 gular. Capsule inclosed in the spatlia, and in- 

 vested with the marresent tube of the corolla, 

 S-relled, many-seeded, opening at the angles; 

 dissepiment contrary. 



Aquatic herbs, nearly allied to the genus Pontederia, 

 having alternate leaves witli a sheathing base. i'lower» 



