262 



BOTANY. 



475. The pollen-cells germinate in moisture by send- 

 ing out a tube which is a prolongation of the inner coat. 

 The protoplasm of the cell passes freely down the tube to 



Fig. 149.— Pollen-cells with roughened walls, 

 erint: Mallow (Lavatera). Highly magnified. 



A, of Chicory ; B, of Flow- 



its extremity, and carries with it both the Tegetation and 

 generation nuclei. 



476. The ovule-bearing leaves of Angiosperms bear still 

 less resemblance to ordinary leaves than do the stamens. 

 In the simpler cases the young leaf becomes curved so that 

 its edges touch and finally grow together, forming the 

 ovary, which usually tapers above into a style or stalk sup- 

 porting a glandular structure, the stigma (Fig. 148, n). 

 The whole ovule-bearing organ, 

 composed of ovary, style, and 

 stigma, is usually known as the 

 pistil. In many plants several 

 ^ -B pistils grow together, and thus 



Fio.m-Very young ovules, form a Compound pistil. 



nc, ovule-body ; sc, inner, and -^ ^ 



fo"' Trfwr'^^'ovuiiriii^ 477. The ovules grow upon the 



Magnified 140 times. ^^^^^ (■_ g__ ^^^^^^ ^^^.j^^^ ^^ ^j^^ 



leaf which forms the ovary, or at its base (Fig. 148), or 

 more frequently upon its margins. At first it is a simple 

 rounded outgrowth of a few cells ; as it grows older a cir- 



