. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. ts of the common pumpkin and of the summer bush squashesare too fibrous and branchy for this test. 3906. It should be stated that the root does not grow at itsvery tip, but chiefly in a narrow zone just back of the tip ; butthe determination of this point is rather too difficult for the be-ginner, and, moreover, it is foreign to the purpose of this lesson. 391. Now let us make a similar experimentwith the stem or stalk. Mark a young stem, as at A in Fig. 341; but thenext day we shall find tha
. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. ts of the common pumpkin and of the summer bush squashesare too fibrous and branchy for this test. 3906. It should be stated that the root does not grow at itsvery tip, but chiefly in a narrow zone just back of the tip ; butthe determination of this point is rather too difficult for the be-ginner, and, moreover, it is foreign to the purpose of this lesson. 391. Now let us make a similar experimentwith the stem or stalk. Mark a young stem, as at A in Fig. 341; but thenext day we shall find thatthese marks are fartherapart than when we madethem (B, Fig. 341). Themarks have all raised them-selves above the ground asthe plant has grown. Thestem, therefore, has grownthroughout its length ratherthan from the end. Thestem usually grows mostrapidly, at any given time,in the upper or youngerportion ; but the part soon The marking of the stem and the ^e^cheS the limit of itSspreading apart or the marks. growth and becomes sta-tionary, and the growth continues beyond it. (SeeSuggestions, p. 48.). PIG. 341. B 6EBMINATI0N OF TBE ONION 323 392. All this behavior of the germinating squashresults in raising the foliage above the soil andin keeping the seed-coats beneath it. But supposethat the seed is not buried, but lies on the sur-face of the moist earth or is covered only withloose leaves or litter: then what happens ? Fill apot or box with earth up to half an inch belowthe rim, lay fresh squash seeds upon it, cover thepot with cardboard, and keep the seeds moist andwarm. Watch the result. Suggestions.—This experiment of germinating seeds upon thesurface is always an interesting one. Peas germinate in this wayvery readily. Whenever this experiment is tried, other seeds ofthe same kind should be planted in the normal way, for compara-tive study. LXII. GERMINATION OF THE ONION 393. A sprouting onion seed is seen in The process further developed is shown inFig. 343. The
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Keywords: ., bookauthorbai, bookcentury1900, bookdecade1900, booksubjectbotany
