SEPT.] FLOWER GARDEN. GREEN-HOUSE. 52t 



the flowers being arrived at maturity, they burst open the spathe in 

 which they are contained, detach themselves from the receptacle to 

 which they are fixed, and rise up to the surface of the water, where 

 they float about as if in search of their mates, and suddenly, with a 

 kind of elasticity, open themselves and discharge their pollen, which 

 being conveyed to the female flowers growing near them, or scattered 

 thereon, impregnates the seeds contained within the germen. 



The pollen being discharged on the stigma, the embryo seeds are 

 impregnated, but how this impregnation is effected it is difficult to 

 say; indeed, while the affair of impregnation in animals is involved 

 in so much obscurity, we can scarcely expect to discover more of it 

 in vegetables. 



It has been the opinion of some of the early writers on the sexes 

 of plants, that the pollen in substance passed through the style, and 

 so impregnated the seeds in the ovary ; but this is a very irrational 

 supposition, for it is not probable that the pollen, which is nothing 

 more than a case for the true sperm, should pass through a part 

 which has every appearance of being impervious to it. 



Whether the sperm itself be conveyed through the style is per- 

 haps what never will with certainty be determined. 



The hint of there being different sexes in plants, seems first to 

 have been taken from the Dicecm class, or such as produce (male) 

 flowers with stamina on one plant, and (female) flowers with pistilla 

 on another. 



" If the dust of the branch of a male palm-tree," says Aristotle, 

 " be suspended over the female, the fruit of the latter will quickly 

 ripen; and if the male dust be carried along by the wind, and dis- 

 persed upon the female, the same effect will follow as if a branch of 

 the male had been suspended over it." 



"Naturalists," says Pliny, "admit of distinction of sex not only 

 in trees but in herbs and all plants; yet this is nowhere more ob- 

 servable than in palms, the females of which never propagate but 

 when they are fecundated by the dust of the male." 



Note. Those who wish to become scientifically acquainted with 

 the Linnaean, or sexual system of plants, will be greatly edified by 

 consulting that very valuable w,ork, the Elements of Botany, pub- 

 lished in 1803 by the late Benjamin Smith Barton, M. D., Professor 

 of Materia Medica, Natural History, and Botany in the University of 

 Pennsylvania. The botanist will also consult Longman and Green's 

 Structural Botany, Gray's Text-Book, and Lindley's School Botany. 



THE GREEN-HOUSE. 



In the eastern States, between the fifteenth and latter end of this 

 month, according to local situations, the nights will be getting cold, 

 and consequently the more tender kinds of green-house plants must 

 be taken in before they change their color by too much cold, leaving 



