Double Fertilization in Compositae

W. J. G. Land
1900 Botanical Gazette  
IN August I898, Nawaschin communicated to the Russian Scientific Congress at Kieff the results of his work on fertilization in Lilium Martagon and Fritillaria tenella. Guignard, upon learning of the discoveries of Nawaschin, contributed to the Academie des Sciences a short account of his unpublished researches upon fertilization in several species of Lilium. Miss Sargant, from a reexamination of her preparations of Lilium Martagon, fully confirmed the observations of both Nawaschin and
more » ... A recent study of Tulipa sylvestris and T. Celsiana by Guignard gives results in strict accord with the earlier observations. These observers find that both male cells upon emerging from the pollen tube are vermiform and twisted on their axes, suggesting the idea of non-ciliated spermatozoids. One male cell, coming in contact with the egg nucleus, retains for a time its vermiform shape, gradually enlarges until it becomes nearly spherical, and finally fuses with the egg nucleus. The other male cell fuses with the upper polar nucleus, and the nucleus resulting from this fusion unites with the lower polar nucleus. Sometimes the polar nuclei fuse and then unite with the male cell, and sometimes the polar nuclei and the male cell fuse simultaneously. Preparations of Lilium Philadelpiicum and L. tigrinum in this laboratory show the last named condition. Miss Sargant figures one case in which the ends of the male cell are applied to the polar nuclei, uniting them as if by a bridge.
doi:10.1086/328039 fatcat:fyii7d2yxvdbjooigjcl7rx4qm