. Lessons in botany. Botany. 198 BOTANY. present the only suggestion which it gives of belonging to the leaf series is the fact that the end is divided into three parts, the number of parts in each successive whorl of members of the flower. If we cut across the body of this pistil and examine it with a low power we see that there are three chambers or cavi- ties, and at the junction of each the walls suggest to us that this body may have been formed by the infolding of the margins of three leaf- like members, the places of contact having then become grown together We see also that from the inc
. Lessons in botany. Botany. 198 BOTANY. present the only suggestion which it gives of belonging to the leaf series is the fact that the end is divided into three parts, the number of parts in each successive whorl of members of the flower. If we cut across the body of this pistil and examine it with a low power we see that there are three chambers or cavi- ties, and at the junction of each the walls suggest to us that this body may have been formed by the infolding of the margins of three leaf- like members, the places of contact having then become grown together We see also that from the incurved margins of each division of the pistil there stand out in the cavity oval bodies. These are the ovules. Now the ovules, we have learned from our study of the gymnosperms, are the sporangia (here the macrosporangia). It is now more evident that this curious body, the pistil, is made up of three leaf-like mem- bers which have fused together, each member being the equivalent of a sporophyll (here the macrosporo- phyll). This must be a fascinating observation, that plants of such widely different groups and of such different grades of complexity should have members formed on the same plan and belonging to the same series of members, devoted to similar functions, and yet carried out with such great modifications that at first we do not see this common meeting ground which a comparative study brings out so clearly. 327. Transformations of the flower of trillium.—If anything more were needed to make it clear that the parts of the flower. Fig. 178. Abnormal trillium. The nine parts of the perianth are green, and the outer whorls of stamens are expanded into petal-like mem- bers. Fig. 179. Transformed stamen of tril- lium showing anther locules on the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original A
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