CLASS HEPTANDKIA. 151 



nu proper corolla ; the six stamens and three pistils are sur- 

 rounded by six sepals, united at the base ; the stipules a^-e of that 

 peculiar kind called ochrea, or boot-like, forming slicaths around 

 the stem above the bases of the leaves. The ColcJdcum autum- 

 nale is allied by many natural characters to the Crocus and 

 Iris. The bulb is a subterranean egg-shaped stem, with the 

 flower, like the Crocus, half hidden in the earth ; the bulb pos- 

 sesses powerful medicinal qualities. In spring several narrow 

 leaves arise, but the flower does not appear till September; 

 the phyton lies buried in the root all winter, and is raised in 

 spring to perfect its seeds before the next season. The flowers 

 are pale purple : this plant is a native of England. 



CLASS Vn. HEPTANDRIA, SEVEN STA:MENS. 



202. Order Monogynia^ onejnstil. — A fine specimen of this 

 class and order is the chick-wintergreen {Tnentalis) ; the calyx 

 has seven sepals, the corolla is seven-parted. One species is said 

 to defend its stamens against injury from rain, by ^losing its 

 petals and hanging down its head in wet weather. There is 

 sometimes to be found in this genus a variation in the number 

 of stamens ; in which case the other parts of the flower also 

 vary. This genus belongs to the great natural order, Primu 

 lacecB. The cultivated Horse-chestnut 

 JEsculus (Fig. 138) is a native of the 

 northern part of Asia, and was intro- 

 duced into Europe about the year 1500 ; 

 it was not probably brought to America 

 until some time after the settlement of 

 this country by Europeans. It is a 

 small tree which produces white flow- 

 ers, variegated with red, crowded to- 

 gether in the form of a panicle ; the 

 whole resembling a pyramid. The blossom is very irregular in 

 its parts ; that is, its other divisions do not correspond with the 

 usual number of stamens ; the stamens, however, do not vary 

 as to number. The seeds have a resemblance to chestnuts, but 

 their taste is bitter. There are several native species of this 

 plant in the Southern and Western States. The horse-chestnut 

 exhibits in its buds the woolly envelope which surrounds the 

 young flowers, the scales which inclose this envelope, and the 

 varnish covering the whole. The stems and branches aftord 

 good subjects for studying the formation and growth of woody, 

 or exogenous stems. The Horse-chestnut is the type of the 

 natural order Hippocastaneoi. 



203. Order Tdrojjyri'i a^ foxir ^nstils. — There is but one plant 



Colchicutn.— 2Q0. What plant is in the first order of ths spvcnth class ?— Horse-chesrnnt. 



