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any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc.

any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc.

One of a class of cellular, flowerless plants, (technically called Lichenes), having no distinction of leaf and stem, usually of scaly, expanded, frond-like forms, but sometimes erect or pendulous and variously branched. They derive their nourishment from the air, and generate by means of spores. The species are very widely distributed, and form irregular spots or patches, usually of a greenish or yellowish color, upon rocks, trees, and various bodies, to which they adhere with great tenacity. They are often improperly called rock moss or tree moss.

A name given to several varieties of skin disease, esp. to one characterized by the eruption of small, conical or flat, reddish pimples, which, if unchecked, tend to spread and produce great and even fatal exhaustion.

One of a class of cellular, flowerless plants, (technically called Lichenes), having no distinction of leaf and stem, usually of scaly, expanded, frond-like forms, but sometimes erect or pendulous and variously branched. They derive their nourishment from the air, and generate by means of spores. The species are very widely distributed, and form irregular spots or patches, usually of a greenish or yellowish color, upon rocks, trees, and various bodies, to which they adhere with great tenacity. They are often improperly called rock moss or tree moss.

A name given to several varieties of skin disease, esp. to one characterized by the eruption of small, conical or flat, reddish pimples, which, if unchecked, tend to spread and produce great and even fatal exhaustion.

One of an order of air-nourished plants or fungi growing on stones, etc.

1. A cryptogamic moss-like plant, forming patches on rocks, tree-trunks, etc.; thought to be algae with parasitic fungi. (The word in this sense is sometimes pronounced lichen.) 2. A general term denoting any papular eruption of the skin, now noting usually 1. planus.

A variety of skin diseases, with papules.

One of an order of cellular flowerless plants: an eruption on the skin.

A cellular flowerless plant.

A flowerless plant growing flat upon a surface, as of a rock.

One of cellular cryptogamous plants, which appear in the form of thin flat crusts, &c., covering rocks and the bark of trees; an obstinate and annoying popular affection of the skin.

The cutaneous affection described under this name by the Greek writers, is not clearly defined. Some have believed it to be Impetigo, but this is doubtful. The name is, now, generally applied to a diffuse eruption of red pimples, accompanied by a troublesome sense of tingling or pricking. Drs. Willan and Bateman define it, - "an extensive eruption of papulae affecting adults, connected witli internal disorder, usually terminating in scurf; recurrent, not contagious." One of their varieties, however, the Lichen Tropicus, does not accord well with this definition; for it affects children as well as adults, and is unconnected with internal disorder.

Any one of a group of plants believed to be composed of symbiotic algae and fungi.

Papular skin-disease of many kinds.

A plant of the Lichenes; of Matthaeus, Cetraria islandica; of the pharmacopeias, Iceland moss.

A dry, papular eruption of the skin.

n. [Latin] One of an order of cellular, flowerless plants, usually of scaly, expanded, frond-like forms;— a cutaneous eruption.