in botany, a genus of the order of fungi, belonging to the cryptogamia class of plants. There are 12 species; the most remarkable of which are,

1. The iperocephalus, or grey round-headed mucor, growing upon rotten wood, and sometimes upon decayed plants and mosses. The stalks of this are generally black; about a line in height, bearing each at the top a spherical ball about the size of a pin's head; its coat or rind is covered with a grey powder, and containing within a black or fulvous spongy down. The coat bursts with a ragged, irregular margin.

2. The lichenoides, or little, black, pin headed mucor. This species grows in groups near to each other, in chasms of the barks of old trees, and upon old park-pales. The stalks are black, about two lines in height; bearing each a single head, sometimes a double or treble one, of the size of mustard or poppy seeds, of a roundish figure at first, but when burst often flattish or truncated, and of a black colour. The internal powdered down is black, with a tinge of green.

3. The mucodo, or common grey mould, grows on bread, fruits, plants, and other substances in a putrid state. It grows in clusters; the stalks a quarter of an inch high, pellucid, hollow, and cylindrical; supporting each a single globular head, at first transparent, afterwards dark grey; which bursts with elastic force, and ejects small round seeds discoverable by the microscope.

4. The glaucus, or grey cluster-headed mould, is found on rotten apples, melons, and other fruits; as also upon decayed wood, and the stalks of wheat. These are of a pellucid grey colour; the stalks generally single, supporting a spherical ball, which, when magnified, appears to be compounded of numerous, fine, moniliform, necklace-like radii.

5. The crustaceus, or fingered mould, is frequent upon corrupted food of various kinds. It is of a white aqueous colour; the stalks single, each supporting at the top four or five necklace-like radii, diverging from the same point or centre.

6. The septicus, or yellow frothy Mucor, is found on the leaves of plants, such as ivy and beech, &c., sometimes upon dry sticks, and frequently upon the tan or bark in hot-houses. It is of no certain size or figure, but of a fine yellow colour, and a substance resembling at first cream beat up into froth. In the space of 24 hours it acquires a thin filmy coat, becomes dry, and full of a footy powder adhering to downy threads. The seeds under the microscope appear to be globular. Haller ranks it under a new genus, which he terms fuligo; the characters of which are, that the plants contained under it are soft, and like butter at first, but soon change into a black footy powder.