THE LOWER FORMS OF LIFE. 



17 



are in our plant feathered. These constitute the female parts of the 

 flower. The male portion, as it is termed, consists of the three 

 stamens (c d). The filament (c) is terminated by an oblong bifid- 

 looking organ (d) ; this is the anther, in which the pollen grains (e) 

 are formed. 



Now the problem to be effected, in order that the grain of wheat 

 should be formed and the race perpetuated, is that the pollen grain 

 (e) should find its way into the ovary (a). The 

 anther (d) opens and casts its pollen upon the 

 stigma (b), which holds it fast there. Observe 

 here that, although the ovary only produces one 

 germ, there are two styles, which is an impor- 

 tant provision to secure the certainty of the 

 production of seed. Well, the pollen grain 

 being caught by the stigma, can get no further, 

 for, though loose in texture, the style is imper- 

 vious. How, then, does the pollen grain get 

 down to the ovary ? Just in this way. The 

 pollen grain, when sticking to the stigma of 

 the style, splits its outer coat (for it is a proto- 

 phytic cell, containing granules, and having 

 two coats). The inner coat then becomes pro- 

 longed in the form of a tube, which pierces 

 the loose cellular texture of the style (Fig. 9), 

 and makes its way down until it reaches the 

 ovary, where it finds a door, termed a micro- 

 pyle, ready open to receive it. In the mean- 

 while the granules which were contained in the pollen grain pass 

 down through this tube, enter the ovary, and there form themselves 

 into cells, which, uniting together, form the ovule or germ of the 

 future seed, with its four protophytic cells, its albumen, and its 

 coverings, as I described when I started on my journey. This pro- 

 cess completed, the young cells are fed with the sugar, formed as in 

 germination by the conversion of starch and which every bee knows 

 how to find ; they thrive, the seed forms and ripens, and again we 

 reach the point from which we started. 



In taking a retrospect of the natural history of our wheat-grain, 

 we cannot exclude from it an expression of the highest admiration at 

 the beautiful adaptation of "vital force," which produces each part 

 of the plant, and prepares it for its designed function. Let us look, 

 for the moment, at one phase in the series alone. We have seen 

 that the leaf is only a modified portion of the stem, and that the 

 flower, with its pistil and stamens, and coloured leaves or corolla, is 

 only a modification of leaves. In this interesting feature of what 



Fig. 9. 



