. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. ller than the other, and the pupilmay infer that it will be crowded out. The factis that the ovary of peaches,apricots, plums and cherriescontains two ovules, but one ofthem commonly aborts ; thatis, it is crowded out, and noremains of it may be seen inthe ripened fruit. When bothovules get an equal start, bothmay persist, and the fruit is double-meated. We maywonder if, in the process oftime, one ovule will be entirelylost. 802. While some plants bearmany pistils in each flower andothers onl
. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. ller than the other, and the pupilmay infer that it will be crowded out. The factis that the ovary of peaches,apricots, plums and cherriescontains two ovules, but one ofthem commonly aborts ; thatis, it is crowded out, and noremains of it may be seen inthe ripened fruit. When bothovules get an equal start, bothmay persist, and the fruit is double-meated. We maywonder if, in the process oftime, one ovule will be entirelylost. 802. While some plants bearmany pistils in each flower andothers only one, we must notconclude therefrom that these features are invari-able. We have already learned that any structureor habit may be broken or changed upon occa-sion. Fig. 246 shows a monstrosity of the peach,five good pistils having formed in one flower. Theprobability is that only one or two of them wouldhave ripened. If two or more should have per-sisted, they probably would have coalesced, and adouble or triple peach would have been the duplication of pistils is not very rare in the. Fig. pistils of peach. SIMPLE PODS 259 peach. It is no doubt a doubling by increase ofparts, as we have seen to take place in someperianths (233). We might speculate as towhether this doubling may be a reversion to someancestral form, or an indication that multiplepistils might become an established character ofthe peach upon occasion; or it may be an inci-dental variation of no significance in the evolutionof the plant. It is certainly evidence, however,that the peach is capable of wide variation inits essential organ. Suggestions.—The pupil should endeavor to make eoUections ofdrupaceous fruits, and should study their sizes, colors and shapes,and especially should notice their number as compared with the flow-ers which bore them. He may be interested to cut them in twoat various stages of growth, to determine at what epoch the mostrapid thickening of the exooarp tak
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