7. _Food of seedlings_.--The food of the Wheat seedling may be shown in fine flour. [1]"The flour is to be moistened in the hand and kneaded until it becomes a homogeneous mass. Upon this mass pour some pure water and wash out all the white powder until nothing is left except a viscid lump of gluten. This is the part of the crushed wheat-grains which very closely resembles in its composition the flesh of animals. The white powder washed away is nearly pure wheat-starch. Of course the other ingredients, such as the mineral matter and the like, might be referred to, but the starch at least should be shown. When the seed is placed in proper soil, or upon a support where it can receive moisture, and can get at the air and still be warm enough, a part of the starch changes into a sort of gum, like that on postage stamps, and finally becomes a kind of sugar. Upon this sirup the young seedling feeds until it has some good green leaves for work, and as we have seen in the case of some plants it has these very early." [Footnote 1: Concerning a Few Common Plants, page 18.] The presence of starch can be shown by testing with a solution of iodine. Starch is turned blue by iodine and may thus be detected in flour, in seeds, in potatoes, etc. After all this careful experimental work the subject may be studied in the text-book and recited, the recitation constituting a thorough review of the whole. A charming description of the germination of a seed will be found in the Reader. V. The Birth of Picciola. _Gray's Lessons_. Sect. II, 8-14. III. _How Plants Grow_. Sect. I, 22, 23. II. III ROOTS. This subject can be treated more conveniently while the young seedlings are still growing, because their roots are very suitable for study. It seems best, therefore, to take it up before examining the buds. 1. _Study of the Roots of Seedlings_.--One or two of the seedlings should be broken off and the slips put into a glass of water. They will be studied later. Bean and Sunflower are the best for the purpose. Begin by telling the pupils to prepare for their first lesson a description of the roots of their seedlings. Those grown on sponge or paper will show the development of the root-hairs, while those grown on sand are better for studying the form of the root. Give them also some fleshy root to describe, as a carrot, or a radish; and a spray of English Ivy, as an example of aërial roots.