Lichens / Liquenes

The distinguished Spanish lichenologist, Reverend Father Longinos Navas, points out and describes in his Synopsis of the Lichens of the Madeira Islands 203 species of these curious cellular plants, which are formed, as is known, by the association of an alga with a fungus. The fungus benefits from the alga's hydrocarbon principles; the alga receives from the fungus protection against desiccation, and a certain amount of nitrogenous substances. This association is called symbiosis. Among the Madeiran lichens, we will mention the following: Stiacta damaecornis, Pseudocyphellaria aurata, Lobaria pulmonaria, Xanthoria parietina, Usnea florida, Nemaria fuciformis, N. rocella, N. fucoides, Cenomyce pyxidata, and different Lecanora, Parmelia, Lecidia, etc.. The three species we have from the genus Nemaria, known by the name of "urzelas", were widely used in the past for the extraction of a reddish-violet substance obtained by fermenting the plants with lime and urine. Lichens are found on tree bark, rocks and walls, soil, etc.. V. Krempelhuber, Stein, Stizenberger, Steiner, Navas.