232 ARISTOLOCHIACE^E. 



Medical Properties and Use*. The bark of white ash has been used 

 with asserted benefit in dysmenorrhsea, but as so many other drugs have 

 attained a short-lived reputation in this affection, only to fall into disre- 

 pute when subjected to more extended experiments, this one may be ex- 

 pected to follow them. Still it appears desirable that the American ashes 

 be investigated, since at least two European species are possessed of valu- 

 able medicinal properties, one of them, F. ornus Linne, furnishing the 

 manna of commerce. Several of our species have been used to some ex- 

 tent, both in domestic and regular practice, but the results are as yet in- 

 definite. 



DIVISION HI. APETALOUS EXOGENOUS PLANTS. 



Corolla wanting, the calyx being the only floral envelope ; sometimes 

 even this is absent, and then the flower is naked. 



ARISTOLOCHIACE/E. 



Character of the Order. Low herbs or twining plants with apetalous, 

 perfect flowers. Calyx valvate in the bud, and coherent with the 6-celled 

 ovary. Stamens 6 to 12, more or less united with the style. Fruit a 6- 

 celled, many-seeded pod or berry. 



A small order of chiefly tropical plants, represented in North America 

 by two genera, namely Asarum and Aristolochia, both comprising medici- 

 nal species. 



ASARUM. WILD GINGER. 



Asarum Canadense Linne. Wild Ginger. 



Description. Calyx bell-shaped, 3-parted, the lobes pointed, abruptly 

 spreading, dull purple inside ; at each sinus is usually a small awl-shaped 

 appendage. Stamens 12 ; filaments slender, united with the base of the 

 styles, the latter united into one, 6-lobed at the summit, with 6 radiating 

 stigmas. Fruit a fleshy, globular pod, bursting irregularly. 



A low, stemless, perennial herb with a creeping rhizome. Leaves a 

 single pair, radical, membranaceous, reniform, more or less pointed, 4 to 

 r> inches wide when full-grown, on long petioles. Flower solitary, on a 

 short petiole, appearing early in spring. 



Habitat. In rich upland woods ; common northward. 



Parts Used. The rhizome and rootlets. Formerly official but dropped 

 from the Pharmacopoeia in 1880. 



Constituents. An aromatic volatile oil and an acrid resin, besides com- 

 mon vegetable principles. 



