sentences:  Originally named in 1801 as "Sclerotium erysiphe" by Christian Hendrik Persoon, the species went through a number of name changes in the 1800s.Salmon's widely used 1900 monograph on the "Erysiphaceae" established the name as "Phyllactinia corylea" for roughly half a century, until the starting date for the naming of fungi was moved, and the name was established as "Phyllactinia guttata".The mycelium may be abundant and persistent, or scant and short-lived ("evanescent").