Genus Peltigera
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The Crescent-shield Lichen. The vegetative portion (thallus) of the Genus Peltigera is leafy and often large; it is veiny and rough, hairy beneath; the algal layer is blue-green, excepting in two species (venosa and aphthosa).
The generic name Peltigera from the Latin pelta, a shield, and gerere, to carry, refers to the fruits which are shield-shaped with a more or less scalloped border; they are borne close to the upper surface of the thallus, usually some distance back from the margin but occasionally on the margin.
The spores are long and narrow, four- to many-celled, at length colourless. It is a small genus of mostly cooler regions.
Dog Peltigera Lichen
Peltigera Aphthosa Lichen