60 THE FLOWER. 



paii'i. But the seeds of this plant are only in embryo, when 

 the fruit itself is nearly full grown, and if taken out and 

 planted, at this time, they will always prove unproductive. 



In those genera of plants which bear their stamens on one 

 tree, and their pistils on another, the same law of nature has 

 been verified in numerous instances. The pollen of one tree 

 must come into contact with the stigma of the other, in or- 

 der that the seeds may come to maturity. The most deci- 

 sive proof of this was established by an experiment so long 

 ago as 1749, made on a Palm tree at Berlin. The Date 

 Palm, like the Fig, Willow, and Poplar, has its stamens and 

 pistils on separate trees, and it so happened that the Palm, 

 at Berlin, was the only tree of that species in the vicinity. 

 It had, therefore, never perfected any fruit, though every year 

 full of flowers which contained the pistils. In the year 

 above mentioned, when the tree was in full bloom, the branch 

 of a staminate tree was sent from Leipsic, by the Post, to 

 Berlin, a distance of twenty German miles, and suspended 

 over the barren Palm. The consequence was, that the tree 

 produced an abundance of fruit that year, which came to full 

 perfection, and many young palms were raised from the 

 seed. Ed. Ency. 



In trees of this class, which are called Di&cious, the pol- 

 len is wafted from the stamens of one, to the pistils of the 

 other, by the wind, or is carried by insects, which fly from 

 one tree to the other in search of honey. As plants of the 

 same species commonly grow in the vicinity of each other, 

 there is no difficulty in conceiving that the prolific influence 

 may be transmitted in this manner. 



The genera which bear their stamens and pistils on the 

 same plant, but in different flowers, are called Monoecious. In 

 these plants the pollen is also transmitted through the air, or 

 by means of insects. Indian Corn is a plant of this kind, 

 the stamej^ being situated in the panicle, or top, while the 

 pistils are .-enclosed in the husk, forming long filaments usu- 

 ally called the silk. Cucumbers, Pumpkins, and Gourds, are 

 also Monoecious plants. 



In various instances we can trace highly curious and in- 

 teresting means employed by nature to apply the pollen to 



What was established by the experiment made on the Palm tree of 

 Berlin ? How is the pollen conveyed from one tree to another where the 

 stamens and pistils are on different trees ? In what common garden ve- 

 getables are the stamens in one flower, and the pistils in another ? 



