SUMMARYProtodontiaandTremellodendronhave the same cytological history as the other genera of the Tremellaceae studied by the writer. The following differences are noted, however. InProtodontiathe epibasidia are definitely affected by the amount of“jelly”surrounding the hypobasidium and vary from very inconspicuous objects found in the flat surface of the fruit-body to long well- developed bodies found in the teeth. In this genus basidia-like sterile bodies occur, each containing only one nucleus and a very scant cytoplasm. InTremellodendron,the fruit-body is composed of three layers: a central mass of densely packed hyphae growing longitudinally in the fruit-body; surrounding this, a layer of radially growing much-branched hyphae; and at the surface a layer of slender tangled hyphae in which are formed the basidia. The basidia do not occur as a continuous layer, but individually. The large fusion nucleus of a mature basidium has the chromatin peripherally located. No abortive structures were observed inTremellodendron.