POLLEN. 79 



If you have paid attention to what has been said respecting the 

 Dolien, you perceive that wonders exist in nature, which are entire- 

 ly unperceived by a careless observer. Who could have imagined 

 mat the yellow dust seen upon the hly or tulip, and scarcely visible 

 upon many other flowers, exhibited appearances so interesting ? It 

 is in part to show you the almost unlimited extent of the field of ob- 

 servation, in the works of nature, that we have dwelt upon this subject. 



Another purpose, and one more connected with our present de- 

 sign, in calling your attention to this subject, is to show the use of 

 tlie pollen in the vegetable economy. You have seen the effect of 

 moisture upon the pollen ; you will recollect that the stigma was 

 said to be imbued with a liquid substance, and that the anther, when 

 ripe, throws out the pollen by the spontaneous opening of its lids or 

 valves ; the pollen coming in contact with the moist stigma, each 

 little sack explodes, and the subtle penetrating substance which it 

 contains, being absorbed by the stigma, passes through minute pores 

 into the germ. 



In the gerni are seeds formed, but these seeds require the agency 

 of the pollen to bring them to the perfection necessary for producing 

 their species. You perceive now why the stamens and pistils are so 

 essential to the perfection of a plant. Nature does not form a beau- 

 tiful flower, and then leave it to perish without any provision for 

 a future plant ; but in every vegetable provides for the renewal of 

 the same. 



The real use of stamens and pistils was long a subject of dispute 

 among philosophers, till Linnffius explained it beyond a possibility of 

 doubt ; these organs have from the most remote antiquity been con- 

 sidered of great importance in perfecting the fruit. The Date 

 palm, which was cultivated by the ancients, bears stamens and pis- 

 tils on separate trees ; the Greeks discovered, that in order to have 

 good fruit it was necessary to plant the two kinds of trees near to- 

 gether, and that w'ithout this assistance, the dates had no kernel, and . 

 were not good for food. 



In the East, at the present day, those who cultivate palms select 

 trees with pistillate flowers, as these alone bear fruit. When the 

 'plant is in blossom, the peasants gather branches of the wild palm- 

 trees, with staminate flowers, and strew the pollen over their culti- 

 vated trees. 



Pistillate flowers are called fertile, staminate, infertile flowers. 



As moisture causes the pollen to explode, rains and heavy dews 

 are sometimes injurious to plants ; the farmer fears wet weather 

 while his corn is in blossom. Nature has kindly ordered that most 

 flowers should either fold their petals together, or hang down their 

 heads when the sun does not shine ; thus protecting the pollen from 

 injury. 



The fertilization of the fig is said to be accomplished by insects. 

 In this singular plant, the fruit encloses the flower; it is, at first, a 

 hollow receptacle, lined with many flowers, seldom both stamens 

 and pistils in the same flg. This receptacle has a smaU opening at 

 the summit. The seeds are fertilized by certain little flies, flutter- 

 ing from one fig to the other, and thus carrying the pollen from the 

 staminate to the pistillate flowers. 



Although the fertilization of plants, where the stamens and pistils 

 are on separate flowers, depends a little upon chance, the favoura- 



Use of the pollen in the vegetable economy— Real use of the stamens and pistils un- 

 known till the time of Linna3us— Cultivation of plants in the East— Flowers fold their 

 netals in wet weather— Fertilization of the fig- Various methods by which nature con- 

 veys pollen to the pistillate plants. 



