Culture Studies of Psilocybe coprophila

Abstract

1. Psilocybe coprophila Fr. has been found to be a heterothallic species producing two strains of primary mycelium, the union of which is necessary for the production of a secondary mycelium with clamp connections, and of basidiocarps. 2. The capacity for the formation of abnormal basidiocarps is greater in some crosses than in others, and is transmitted from generation to generation, although not as a simple Mendelian character. 3. Oidia are produced on both primary and secondary mycelia. Those produced by primary mycelia germinate to form haploid mycelia of the same strain as the parent culture. Those produced by secondary mycelia sometimes germinate to form diploid mycelia. At other times they germinate to form haploid mycelia, segregation of nuclei occurring before the oidia are produced. This segregation seems to take place less readily in cultures of polysporous origin than in a diploid mycelium formed by crossing two primary strains.