It was in the 19th Century that the true nature of lichens, as organisms consisting of an alga and a fungus in specific association, was demonstrated by Schwendener in 1867. This removed a source of confusion in morphology and classification (Morton, 1981 p. 432).[1] It was in this period (1859) that Charles Darwin (1809–1882) published his book on evolution:On the Origin of Species by Means of Natural Selection,....