FECUNDATION. 135 



CHAPTER VIII. 



ON THE ESSENTIAL AND CONSECUTIVE PHENOMENA OF 

 REPRODUCTION. 



The process of fecundation appears to be as follows : 

 As soon as the calyx and corolla are expanded, the stamens 

 free from all confinement take a rapid development, and 

 the anthers up to this time unruptured, moist, and closed, 

 become dry, and opening their cells, discharge the pollen 

 over the stigmar, and very frequently over the other parts 

 of the flower. The stigma, or apex of the pistil, is about this 

 time bedewed with a clammy fluid, which serves to retain 



Fig. 27. 



Triangular pollen grain of the evening primrose, (QSnothera,) with one pollen 

 tube t, protruded. This tube is formed by the intine, which is also seen pro- 

 jecting at the other angles. 



the grains of pollen on its surface. The grains of pollen, 

 after remaining for some time on the humid stigma, absorb 

 its moisture, and are seen to swell, so that those which are 



