Eighteen small lentiginous nevi, each 1-3 mm in diameter, showed aggregates (nests) of melanocytes in the lower portion of the epidermis. In six of the 18 nevi, nests of melanocytes were evident only after examination of numerous serial sections (approximately 100-125). These six lesions would have been diagnosed as simple "lentigines" if the serial sections had not been examined. Lesions referred to as simple "lentigines" may actually be lentiginous nevi.