164 . CLASS POLTANDRIA. 



merce. The juice which issues fi'om incisions in the gr«en cap- 

 sules is dried in the sun, and made into cakes. Tlie narcotic 

 property of opium renders it highly valuable as a medicine. 



232. The genus Citrus contains the orange, lemon, lime, 

 citron, shaddock, &c. Oil abounds in the leaves and rind of 

 the fruit. The lemon, lime, and citron are distinguished from 

 the orange by their oblong form, their adherent rind, and a 

 protuberance at the apex. The oil of hergamot is obtained 

 from the rind of a small fruit of this genus. The Citrus is 

 subject to an abnormal separation of the carjDcls, which pro- 

 duces what are called horned oranges, an^ fingered citrons, and 

 in some cases to a multiplication of the normal number of car- 

 pels, in which case an orange is formed within an orange. 

 Jussieu placed this in his order Aura7itia, or golden fruits, 

 now called Aw^antiacece. The fruit is a berry with a thick 

 coat ; it furnishes citric acid. 



233. Order Dijpentagynia, — The four orders following Mono 

 gynia are, as in the preceding class, united into one, called, as 

 before, Dipentagynia, having from two to five styles. We 

 find here some plants of a poisonous nature, as the larkspur, 

 monk's-hood, and the columbine ; these belong to the natural 

 order Raniinculaceoe^ the type of which is the ranunculus or 

 crow-foot. The p?eony {Pceo7iia)^ a large and showy flower, 

 which in its simple state has five se^^als, five petals, two or 

 three ovaries, each crowned by a stigma ; carpels the same in 

 number as the ovaries, each containing several seeds : this 

 flower is remarkable for becoming double by cultivation. 



234. Order Polygynia. — ^Tlie Clematis virginiana is a com- 

 mon American plant ; the stem supports itself on shrubs and 

 trees by means of its long petioles, which serve as tendrils. 

 At Fig. 143, «, is a flower of the Clematis ; h represents its 

 receptacle with numerous styles proceeding from it, and the 

 petals and stamens separated from their insertion upon the 

 receptacle. The Hellebore {Helleborus) is an exotic much 

 spoken of by classical writers. Hipj^ocrates, one of the most 

 ancient physicians, remarked upon its qualities ; it grew about 

 Mount Olympus, and was early known as a very poisonous 

 plant. The Magnolia and Tulij)-tree are among the most 

 splendid trees of North America. In some cases these trees 

 rise to the hight of ninety feet before sending ofi" any con- 

 siderable branches ; tlie spreading top is then clothed with 

 deep-green, oblong-oval leaves ; they have large and fragrant 

 white flowers. The class Polyandria contains many valuable 

 medicinal plants, but few important fruits. 



232. Genus Citrus.— 233. Order Dipentagynia— Natural order Ranunculacea— Pseony.— 234. Order 

 Polygynia— Clematis— Hellebore — Magnolia. 



