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Keywords from Image Description:
Haeckel Lichenes. Assessments Lichen sketch See mpizkoeln mpg de html here for index to numbers Cladonia retipora Floerke Labill Nyl Hooker Achard Hoffm Ahti Hoffmann Scop Hoffm Fries Fr Fries Achard Hoffm Fries non Ach preoccupied Ehrh ex Humb Frnr Achard Essl Achard Hale Schleicher Schleich Vzda Kunstformen