PSORALEA. 131 



scattered, on long petioles ; leaflets of the lower leaves nearly orbicular, of 

 the upper narrow, often linear. 



Habitat. Cultivated and waste places. Introduced from Europe. 



Melilotus alba Lambert. White Melilot. 



Description. Very closely resembling the preceding, except that it has 

 white flowers and is a somewhat larger plant. 



Habitat. Cultivated and waste places. Introduced from Europe. 



Part Used. The herb not official. 



Constituents. These plants in drying have a fragrant odor, due to the 

 presence of coumarin the important constituent of Tonka beans ; and they 

 are only interesting on this account. 



Preparations. There are none. 



Medical Properties and Uses. Yet to be determined. That coumarin 

 exerts a decided influence upon the heart is well known, and hence all 

 plants in w T hich this principle is found are not without interest, especially 

 those which are or are likely to be used as adulterants of smoking tobacco. 

 There is good reason for believing that many of the ill effects of cigarette- 

 smoking, so common among our boys and young men, are due, not to the 

 tobacco, but to the presence of adulterants containing coumarin. (See also 

 Liatris odoratissima.) 



PSORALEA. 



Character of the Genus. Calyx deeply 5 -cleft, the lower lobe longest. 

 Stamens diadelphous, or occasionally monadelphous. Pod about the length 

 of the calyx, indehiscent, 1-seeded, sometimes beaked. 



Shrubs or herbaceous perennials, commonly dotted with prominent 

 glands or points. Leaves 3- to 5-foliate. Flowers in spikes or racemes, 

 white, blue, or purple. 



Psoralea melilotoides Michaux. 



Description. Calyx : teeth triangular-ovate. Pod orbicular, trans- 

 versely wrinkled. Herbaceous, sparingly pubescent, glandular, 1 to 2 

 feet high. Leaves 3-foliate ; leaflets oblong-lanceolate, dotted, about 2 

 inches long. Spikes oblong, on peduncles three to four times as long as 

 the leaves ; flowers one-fourth inch long, usually in pairs on short pedicels, 

 appearing in May and June. 



Habitat. Dry soil, Ohio, Illinois, and westward. 



Psoralea esculenta Pursh. 



Description. Calyx : teeth lanceolate, a little shorter than the corolla. 

 Pods beaked. Herbaceous, hairy, about 1 foot high. Root thick and fusi- 

 form, about the size of a walnut. Leaves 5-foliate, slightly dotted ; leaflets 

 lanceolate. Spikes dense, on long peduncles ; flowers pale blue, one-half 

 inch long, appearing in June or July. 



Habitat. High plains from Wisconsin westward. 



Parts Used. The leaves and root not official. 



