Tin' 



and Its Parts: 



<>/ Fi-rtnizuCwn. -'.' 



11. Staminte. 

 of the 

 Oak i'ii. 



of the blossom is secured whenever the pollen, at maturity, is con 

 veyed to the stigma of the pistil. 



117. 'The blossoms of trees are often unsymmetri- 

 cal, and the parts essential to fertilization may be 

 either in the same blossom, as shown on a subsequent 

 page in the linden, or on different parts of tin- same 

 tree, as shown in the hornbeam and the alder, in the 

 accompanying engravings. In the latter, the germs 

 for the early spring blossoms are formed the fall In-- 

 fore. Such pendant blossoms in tiv.-s are railed 

 aiii''iit.-t, or ftfldns. Their form and struetiire afford 

 characters, upon which botanical da>.-ification in part 

 depends. 



118. Where both the staminate and pistillate blos- 

 soms grow upon the same plant, it i< -aid to be 

 monoecious, but when formed upon different trees or 



plants, as in case of the poplars and willows, it is -aid to be diccc imin . 

 In the latter case, the seeds can not be fertile, unless trees hearing 

 both kinds of blossoms grow 

 in the same neighborhood* 



119. The winds have an 

 important influence in dis- 

 seminating the pollen from 

 one tree to another, and the 

 blossoms of such trees gen- 

 erally open in the windy sea- 

 son of the year, and before 

 the leave* appear. The bees, 

 in pursuit of honey, perform 

 an important office in con- 

 veying pollen from one blos- 

 som to another, and there 

 are many special arrange- 

 ments in nature for securing 

 fertilization. 



120. When the pollen of one species is conveyed to the pistillate 

 flowers of another species, within the same genus, cross-fertilization 

 sometimes occurs. This may occur naturally, or by artificial means, 



1J. Two Mule Blossoms of the Hornbeam, and 

 the Terminal Pistilate Ulossom. 



