Cell Division by Furrowing in Magnolia

In ''Les centres cintiques chez les Vgtaux'' (8), published in 1897, L. Guignard supported his previous contentions as to the existence of centrosomes in Angiosperms by studies on the reduction divisions of certain Dicotyledons, namely: Nymphaea, Nuphar, Limodorum, and Magnolia. Although most cytologists are unwilling to admit that Guignard succeeded in establishing his thesis, yet this must be recognized as a very critical piece of work, involving nearly one hundred careful drawings which bespeak excellent fixation. His