A strain of L. tigrinum exhibited frequent lagging of 1 pair of chromosomes at the 1st meiotic ana phase of pollen mother cells. Less frequently, lagging of 2 pairs occurs. A lagging chromosome frequently becomes caught in the developing partition wall and a piece of chromosome may become abstricted. The poleward stresses of anaphase separation may separate sister chro-matids, or portions of 1 chromatid. Two homologues occasionally become incorporated in the same daughter cell. Four full-sized microspores are produced. The subsequent development of gametophytes and gametes was not studied.