STUDIES OF CANADIAN THELEPHORACEAE: VI. THE PENIOPHORA RIMICOLA GROUP

In the following contribution four species of Peniophora are described, illustrated, and discussed, which appear to represent a closely related group. These are Peniophora rimicola (Karst.) Hohn. & Litsch., P. pruinosa (Pat.) comb. nov., P. pulverulenta (Litsch.) comb. nov., and P. praeterita proposed as a new species. These species have several characters in common. All are mucous-gelatinous when fresh, drying to a vernicose film. In all of them simple, capitate, or apically lobed cystidioles are present and the spores show some degree of roughening when mounted in Melzer's solution. All but one, P. pulverulenta, have long emergent cystidia which may be slightly thickened at the base.