My Studio Neighbors

In 1682 Nehemias Grew announced to the scientific world that it was necessary for the pollen of a flower to reach the stigma or summit of the pistil in order to insure the fruit. I have indicated his claim pictorially at A (Fig. 3), in the series of historical progression. So radical was this "theory" considered that it precipitated a lively discussion among the wiseheads, which was prolonged for fifty years, and only finally settled by Linnaeus, who reaffirmed the facts declared by Grew, and verified them by such absolute proof that no further doubts could be entertained. The inference of these early authorities regarding this process of pollination is perfectly clear from their statements. The stamens in most flowers were seen to surround the pistil, "and of course the presumption was that they naturally shed the pollen upon the stigma," as illustrated at B in my series. The construction of most flowers certainly seemed designed to fulfil this end. But there were other considerations which had been ignored, and the existence of color, fragrance, honey, and insect association still continued to challenge the wisdom of the more philosophic seekers. How remarkable were some of those early speculations in regard to "honey," or, more properly, nectar! Patrick Blair, for instance, claimed that "honey absorbed the pollen," and thus fertilized the ovary. Pontidera thought that its office was to keep the ovary in a moist condition. Another botanist argued that it was "useless material thrown off in process of growth." Krunitz noted that "bee-visited meadows were most healthy," and his inference was that "honey was injurious to the flowers, and that bees were useful in carrying it off"! The great Linnaeus confessed himself puzzled as to its function.