Meiosis and ascospore genesis in Neurospora

McClintock [38] and Singleton [69, 70] first described and documented the meiotic sequence in neurospora crassa with particular emphasis on the chromosome cycle. In recent years different methods have been used that yield greatly improved cytological preparations. This review provides an integrated description of normal meiosis and ascospore genesis for all eight-spored Neurosporas with photographs of asci stained with iron-hematoxylin. In addition, maturing asci from crosses with selected mutants and a chromosome rearrangement are illustrated. Some novel observations and interpretations are given briefly in the text. It is hoped that this presentation will provide a useful reference, comparable to the photographs of maize meiosis published by Rhoades [59, 60].