The studies involved in this investigation are based upon data and materials secured in the sandy areas of Washington and Iron Counties in southern Utah. The regions in which Yucca angustissima is found have a scant vegetation, are dry, sandy to sandy loam, well-drained, and with an elevation of from 2500 to 5000 feet. Watkins (1937) worked out a very extensive report of the megagametophyte development of Yucca rupicola. He begins with the four megaspore stage, and shows next the disintegration of the three micropylar megaspores. He reported that the chalazal megaspore forms eight free nuclei, by three successive divisions, to form the mature megagametophyte. His report "conforms in general to that of Folsom and included certain additional intermediate developmental stages.'' This investigation, with a few variations, corroborates the findings of both Folsom and Watkins.