The fungi with teeth are so called because, instead of bearing their spores on the surface of gills and pores, they bear them on the surface of awl-shaped teeth, which project downward. The genera of the family Hydnacece are distinguished by the size, shape, and attachment of the teeth. Plants with teeth only, and no basal membrane, make the genus Mncronella. Plants with flattened, leaf-like teeth attached to a leathery membrane, growing on wood, either in the form of a cap, or simply spreading over the host, make the genus Irpex. Plants with thick, blunt, irregular spines make the genus Radulum. Fleshy or membranous plants with caps and flattened teeth, growing on the ground, make the genus Sistotrema. Plants which spread over their host, closely attached to its surface, and have simple, bristle-like teeth, make the genus Pycnodon. Plants growing in a manner similar to those of the genus Pycnodon, but having low-crested wrinkles instead of bristles, make the genus Phlebia; while those with smooth hemispherical warts make the genus Grandinia, and those with crested papillose warts make the genus Odontium. The typical genus Hydnum has the teeth cylindrical, so that a cross section would appear circular. This is the only large genus, and in it are found several important edible species. These may be put in two groups, one containing the species with a cap and central stem, and one the species growing in branched masses with no distinct cap. These are commonly known as Hedgehog Mushrooms.

Hyd-na-ce.ae Ir-pex Sis-to-tre'-ma Phleb-T'-a

Mu-cro-nel'-la Rad'-u-lum Pyc'-no-don Gran-dl'-ni-a

O-dont'-l-um Hyd'-num