The proposed research consists of two projects: (1) It has been observed in Lilium 'Croft' and 'Ace' that laggard cells in premeiotic mitosis do no complete this division; the chromosomes despiralize to interphase and the cells enter into meiosis. It was proposed that the mitotic divisions could not be completed because the reproductive organ (anther) had reached a state of physiological preparedness for meiosis, or "meiosis readiness". An excess of cells in premeiotic prophase indicated a slow-down of this division as meiosis approached. Premeiotic slow-down and premeiotic despiralization may be related causally. This suggestion is supported by observation in the distantly related Lilium 'Enchantment' that premeiotic slow-down is comparatively slight and premeiotic despiralization absent. Additional Lilium cultivars are being examined for these characteristics. (2) Preleptotene chromosome contraction has been observed in a considerable number of animals and plants. The significance of this stage has not been established. It has been proposed that the degree of chromosome contraction depends on the duration of the contraction phase. It has recently been observed that first- and last-developing buds of individuals of L. 'Enchantment' differ markedly in degree of preleptotene contraction. It is suggested that first and last buds, representing the beginning and end of the reproductive life of the individual, may differ correspondingly in rate of meiotic division. Preleptotene chromosome contraction will be compared in first- and last-developing buds of Lilium longiflorum 'Ace'.