TEE WORK OF FLOWERS 311 



the orchard Fig (which is the seed- bearing plant) tiny 

 wasps, all covered with pollen, creep out of the capri- 

 figs and enter the edible figs, and so pollinate the flow- 

 ers, which consequently are enabled to set seed. It is the 

 seed which gives to the Smyrna Figs the peculiar nutty 

 flavor which makes them so valuable for the market. 



The Smyrna Figs do not develop fruit without fer- 

 tilization: they contain true seeds. The Mission Fig 

 of California and other varieties which develop fruit 

 without fertilization have no true seeds, but only hollow 

 shells containing no embryos. 



For a long time there has been a belief that the pol- 

 len can not only stimulate the growth of the seed- case 

 and surrounding parts but also influence their color, 

 form, etc. (this phenomenon is known as Xenia). A 

 white Corn pollinated with a dark Corn produces in 

 'the course of the same summer an ear with white and 

 dark kernels mingled, giving the ear a very curious 

 appearance. Examination shows that in this case it 

 is not the seed -case whose color is affected but the 

 seed itself; it is the endosperm of the seed which is 

 colored, and this arises from a nucleus which, like the 

 Qg^ nucleus, fuses with a nucleus from the pollen -tube 

 (Fig. 164), and so can receive the qualities of the pol- 

 linate parent. Many different kinds of evidence go to 

 show that the nucleus is the bearer of hereditary 

 qualities, and that where two nuclei fuse the resulting 

 nucleus bears the qualities of both, 



