NAT. ORDER. 



Z^guminoscB. 



INDIGOFERA VIOLACEA. PURPLE INDIGO PLANT. 



Class XVII. DiADELPHiA. Order IV. Decandria. 



Gen. Char. Calyx, five-cleft. VcxUlum, roundish, emarginate : — 

 keel furnished with a subulated spine on each side. Slaniens, 

 diadelphous. Styles, filiform. Legume, continuous, two-valved. 



Spe. Char. leaves, various, usually iiTegular, pinnate, or digitate, 

 Stijmlcs, small, not united with the petiole. Flowers, in axillary 

 racemes, purple, blue or white. 



This plant has a root which is perennial, irregular, large and 

 woody, blackish outside, yellowish within, and sending off many slen- 

 der branches or fibres. The stems are two or three feet high, round 

 and smooth, of a yellowish-green color, with black spots, very much 

 branched at the top ; the leaves are alternate, small, somewhat heart- 

 shaped, and broadest towards the outer end ; the blossoms are of a 

 puiple or white color, sonne species have a yellow flower, and are suc- 

 ceeded by a swelled oblong pod, of a bluish or blackish hue, as indeed 

 is the whole plant, and becoming quite black on drying ; the taste of 

 the root is unpleasandy subacrid and nauseous. 



This shrub is cultivated mostly in warm climates in dry steiile 

 soils. In North Carolina, Florida and Arkansas, it is raised in large 

 quantities as an article of trade. 



Sensible ami Chemical Properties. A well-known and highly 

 important dye-stulTis obtained from this and other species of the Iii- 

 di^ofcra. In the process of preparing it, the plant is macerated in 

 water ; fermentation takes place ; tlie liquor becomes of a greenish 



Vor,. III.— 133. 



