98 



Principles of Plant Culture. 



smaller and more delicate upper or inner palets wkicli 

 are just above and inclosed within the outer palets. 

 Between the outer and inner palets are the stamens and 

 pistils, shown separately in Pig. 55. 



b'^' 



Fig. 53. Fig. 54. FiG. 55. 



Fig. 53. Spikelet of wheat; st, stamens. (After La Maout and Deoaisne). 



Fig. 54. The same dissected; x, axis of spikelet; g, glumes; bj, b^, 

 outer pales; B^, Bg, flowers displaced from the axis of outer pales; p s, 

 inner pales; a, anthers; f, ovary. (After Prantl). 



Fig. 55. Flower of wheat, enlarged; st, stamens; p, pistil; o, ovary. 

 (After La Maout and Decaisne). 



150. Fecundation (fec'-un-da'-tion) is the union of the 

 male and female cell by which the new plantlet is formed. * 

 The ovule produces within itself a female cell which 

 may be fecundated by the male cell produced by the 

 pollen (144). This fecundated cell then grows to form 

 a young plant — the embryo (56), and the parts of the 

 ovule develop about it, the whole forming the perfect 

 seed. Unless the ovule is fecundated, the seed very 

 rarely develops. A flower that contains no pistil and 

 hence no ovule, can of course produce no seed. 



151. Pollination (pol-lin-a'-tion), is the access of pollen 

 (144) to the stigma (145) — the first step in the process 



* The term fertilization (fer-til-i-za'-tion), that has been commonly used 

 for this process, tends to confusion, because this term is also applied to 

 the addition of plant food to the soil. 



