Cover photograph (Copyright © 2006, American Society for Microbiology. All Rights Reserved.): Psilocybe coprophila (Agaricales) fruiting on a petri dish of potato dextrose agar, approximately 3 weeks after inoculation (magnification, ∼3×). A ribosomal DNA sequence corresponding to this species was PCR amplified from soil at the Kellogg Biological Station Long-Term Ecological Research site near Battle Creek, Michigan, along with DNAs of 240 other species of mushrooms. Photograph by R. G. Thorn. (See related article on page 7050.)