The seborrheic variety spreads from the scalp to the folds of the skin.
seborrheic seb·or·rhe·ic (sěb'ə-rē'ĭk)
Of, relating to, or affected by seborrhea.
seborrhea seb·or·rhe·a or seb·or·rhoe·a (sěb'ə-rē'ə)
Overactivity of the sebaceous glands characterized by excessive secretion of sebum or an alteration in its quality, resulting in an oily coating, crusts, or scales on the skin.