CLASSIFICATION OF ANGIOSPERMS. 375 



The root and berries are used in medicine. The root is simple 

 and quite long, 5 to 10 mm. in diameter, yellowish-brown, the 

 bark readily separating from the wood. It has a narcotic odor 

 and a sweetish, bitter, somewhat acrid taste. Both the root and 

 berries contain the gluco-alkaloid solanine, which varies' from 0.15 

 (in the root) to 0.8 per cent, (in the berries). 



Capsicum fastigiafinii (Cayenne pepper) is a perennial, 

 smooth, herbaceous, or somewhat shrubby plant, with ovate, acu- 

 minate, petiolate, entire leaves ; the flowers are greenish-white, 

 and solitary in the axils of the leaves. The fruit is official and is 

 known in commerce as African pepper (p. 578). This plant 

 and a number of other species of Capsicum are indigenous to trop- 

 ical America, where they are extensively cultivated, as also in 

 Africa and India. 



Nicotiana Tabacnm (Virginia Tobacco plant) is a tall annual 

 herb indigenous to tropical America and widely cultivated. The stem 

 is simple, giving rise to large, pubescent, ovate, entire, decurrent 

 leaves, the veins of which are prominent and more or less hairy. The 

 flowers are long, tubular, pink or reddish, and occur in terminal 

 spreading cymes. The various forms of tobacco are made 

 from the leaves, which are hung in barns, whereby they 

 undergo a slow drying or process of curing. Other species of 

 Nicotiana are also cultivated, as A^ pcrsica, which yields Persian 

 tobacco ; and ^V. nistica, the source of Turkey tobacco. Tobacco 

 leaves contain from 0.6 to 9 per cent, of the alkaloid nicotine ; an 

 aromatic principle nicotianin or tobacco camphor, to which the 

 characteristic flavor is due and which is formed during the curing 

 of the leaves. The dried leaves yield from 14 to 15 per cent, of 

 ash, consisting in large part of potassium nitrate. 



Solanuvi tiibcrosuni (Potato plant) is indigenous to the Andes 

 region of South America and is extensively cultivated on account 

 of the edible tubers. The tubers (potatoes) contain about 75 per 

 cent, of water, 20 per cent, of starch, and nearly 2 per cent, of 

 proteins in the form of large protein crystalloids. The fruits and 

 young shoots contain the gluco-alkaloid solanine and the alkaloid 

 solanidine. The tubers contain a small amount of solanine, which 

 is increased when they are attacked by certain fungi or exposed 

 to light. 



