I'l-h'Tifjs.rnoy i(;(> 



hours in a dark place, it will he fit for our 

 iniiposc. 



When placed in the microscope we shall observe 

 that man}' of the t^rains w ill ha\e thrown out lon<j^ 

 thread-like tubes, and this is just what happens 

 when pollen falls u|)on the \iscid stit^ma of the 

 lil\-. keferriiiL;' to the section of a lil\' pistil we 

 see that a pollen ^rain has rested on the stigma, 

 and, excited into growth 1)\- the sweetish lluid 

 which holds it there, it sends down a slender tube 

 through the centre of the pistil, which is lined with 

 a very delicate loose tissue of cells filled with 

 starch, oils and food-materials. The pollen-tube 

 is stimulated and fed b)- this nourishment stored 

 up in the conductiuL!; tissue, and on it L;oes until, 

 passing throui^h the micropyle, it enters the 

 embryo-sac of one of the ovules, adheres to it, and 

 renders it fertile. 



Only one ^rain is shown in the drawin<;' for the 

 sake of clearness, but of cour.se each ovule is 

 sought out and fertilised b\- a pollen-tube. With 

 infinite \ariation this process takes j:)lace in e\'er\- 

 flower, so that even the commonest weed affords 

 evidence of the mar\ellous provisions made by 



