;o6 A TEXT-BOOK OF BOTANY. 



ripe; Soft-leaved arrow-wood (V . molle), which somewhat re- 

 sembles V . dentatum, but has larger leaves that are crenate or 

 dentate and stellate-pubescent on the lower surface ; Larger withe- 

 rod (V . mtdum), having nearly entire leaves and a pink drupe, 

 which becomes dark blue. 



Sambucus canadcnsis (American elder) is a shrub growing 

 in moist places in the United States as far west as Arizona and 

 in Canada. The leaves are 5- to 7-foliate, the leaflets being ovate, 

 elliptical, acuminate, sharply serrate, and with a short stalk ; the 

 flowers are small, white, and in convex cymes. The fruit is a 

 deep purple or black berry-like drupe. The dried flowers are used 

 in medicine. They are about 5 mm. broad, with a 5~toothed, 

 turbinate calyx, and a 5-lobed, rotate corolla, to which the 5 sta- 

 mens are adnate. The odor is peculiar and the taste is muci- 

 laginous and somewhat aromatic and bitter. 



The active principles have not been determined, but are prob- 

 ably similar to those of 5. nigra. The inner bark is also used in 

 medicine and contains a volatile oil, a crystallizable resin, and 

 valerianic acid. It does not appear to contain either tannin or 

 starch. The roots of elder contain a volatile principle somewhat 

 resembling coniine. The pith consists chiefly of cellulose, is deli- 

 cate in texture and has a variety of uses (Fig. 132). 



The Black elder (Sauibucns nigra), which is a shrub com- 

 mon in Europe, is characterized by narrower leaflets, a 3-locular 

 ovary, and black berries. The flowers are official in some of the 

 European pharmacopoeias. They contain about 0.4 per cent, of 

 a greenish-yellow, semi-solid volatile oil, which when diluted has 

 the odor of the flowers. They also contain an acrid resin. 



The Red-berried elder or mountain elder (S. pubois] some- 

 what resembles the common elder, but the stems are woody, and 

 the younger branches have a reddish pith. The flowers are in 

 paniculate cymes, and the fruits are scarlet or red. 



Other plants of the Caprifoliacere are also used in medicine. 

 Horse gentian (Triosteum perfoliatum), a perennial herb with 

 connate-perfoliate leaves and small, orange-red, globular drupes, 

 growing in Canada and the United States as far west as Kansas, 

 furnishes the drug (rhizome) known as WILD IPECAC or Trios- 

 teum. The rhizome is yellowish-brown, somewhat branched, 



