Elementary botany . elementarybotany00atki Year: 1898 is spin\'. They are in faet spores, the microspores of the trillium, and here, as in the gymnosperms, are better known as pollen. Fig. 291. Sepal, petal, stamen, and pistil of Trillium grandi riorum. 444. The stamen a sporo- phyll.—Since these pollen grains are the spores, we would infer, from what we have learned of the ferns and gym- nosperms, that this member of the flower which bears them is a sporophyll ; and this is the case. It is in fact what is called the microsporophyll. Then we see also that the anther sacs, since they enclos
Elementary botany . elementarybotany00atki Year: 1898 is spin\'. They are in faet spores, the microspores of the trillium, and here, as in the gymnosperms, are better known as pollen. Fig. 291. Sepal, petal, stamen, and pistil of Trillium grandi riorum. 444. The stamen a sporo- phyll.—Since these pollen grains are the spores, we would infer, from what we have learned of the ferns and gym- nosperms, that this member of the flower which bears them is a sporophyll ; and this is the case. It is in fact what is called the microsporophyll. Then we see also that the anther sacs, since they enclose the spores, would be the sporangia (microsporangia). From this it is now quite clear that the stamens belong also to the leaf series. They are just six in number, twice the number found in a whorl of leaves, or sepals, or corolla. It is believed, therefore, that there are two whorls of stamens in the flower of trillium. 445. Gynoecium.—Next above the stamens and at the center of the flower is a stout, angular, ovate body which terminates in three long, slender, curved points. This is the pistil, and at
Size: 1295px × 1544px
Photo credit: © Bookend / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: archive, book, drawing, historical, history, illustration, image, page, picture, print, reference, vintage
