Anthers for Wind Pollination
Zygocactus truncatus is a good example of a species in which the stamens hang free from the perianth, suggesting wind, rather than insect pollination. Fig. a shows the relationship of the stamens to the whole flower, while Fig. b, a close-up of the anthers and stigma, gives an indication of the number of stamens (ca. 50) and the quantity of pollen produced. When dissected out of the flower, (Fig. c) the filaments are found to be ca. 2"/50 mm long and make a striking contrast with those of insect pollinated Hyacinthus orientalis.
The arrangement and number of the stamens, the amount of pollen and the absence of scent are all pointers towards wind pollination, as are the narrowness and length of the tube; it would take a rather small and very determined insect to push its way that distance, through such a crowded mass of filaments.
