sphærotheca

Century Dictionary and Cyclopedia

1. n. A genus of pyrenomycetous fungi, belonging to the family Erysipheæ, characterized by a perithecium which contains only a single ascus. The appendages are simple threads not unlike the mycelium with which they are frequently interwoven. The ascus is usually suborbicular in shape, and generally contains eight spores. S. humuli, called the hop-mildew, is destructive to the hop-vine; S. pannosa is injurious to rose-bushes; and S. mors-uvæ is the common gooseberry-mildew. See hop-mildew.