Physcia Leucomela Lichen
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Habit and habitat.-On trees, most common southward.
Vegetative organs (thallus). - Ascendant and elongated, mostly smooth, often narrowly linear, the densely entangled lobes irregularly divided; beneath white, the margins beset with strong, branched blackish fibrils.
Fruiting organs (apothecia).--Medium-sized, on short pedicels, the disk white, powdery, the border lobed; the spores are bilocular.
Name.-From the Greek; white, and black, referring to the strong contrast between fibrils and surface.