The monocot Lilium, possessing very large nuclei and chromosomes, is a favorable material for studying problems of development, parti cularly with regard to the proteins of the nucleus (Sheridan and Stern, 1967). Since it would broaden the possible approaches to such study if successful, an attempt was made to establish Lilium in tissue culture. This communication reports (1) the successful establishment in both agar and liquid shake cultures of callus of Lilium longiflorum Thunb ; (2) the repeated subculturing of the callus on growth factor free media; and (3) the production of large numbers of plantlets from callus under certain growth conditions in liquid suspension cultures. Callus was established by placing tissue expiants from steBi apices onto the basal medium supplemented with 2 mg/1 of indoleacetic acid (IAA). The terminal 10 cm of stems which were approximately 25 cm in height were removed and all but the smallest leaves were stripped off. The apices were washed for 5 min in a solution of the detergent Heikol, 10 min in 10% Clorox, and 5 min in sterile distilled water. Each apex was then placed in a sterile petri dish and the outer portion in cluding all the leaves and primordia was removed with a sc^pel leaving a cylinder which was free of any surface tissue. The terminal 2 cm were removed and placed on the medium. The basal medium was that of Linsmaier and Skoog (1965) con taining major and minor salts, organic supplements of thiamin and inositol, and 40 g of sucrose per liter. Basal agar medium refers to the above medium solidified with 0.8% agar. Fresh weight was used for determining growth response. Within three weeks of explantation, callus appeared on the edge of the tissue block in contact with the medium. The presence of IAA in the culture medium stimulated the production of callus by the stem tissue but was not essential for it. When expiants were placed on medium lacking IAA, buds appeared on the surface of the tissue blocks and shoots and roots were formed producing new plants; on occasion callus was also formed, but usually only after the formation of roots and shoots.