In order to search an extract from the liquid culture of myceliurn of Polyporus um- hellatus（Pers）Fr.to be used as a substitute for the crude material and produced indus- trially in a large scale

studies have been made on the isolation of the fungus from natural sclerotia

methods of the liquid cuhure of the vegetative mycelium and its antitumor action. The white vegetative mycelia isolated from the sclerotia are secondary mycelia with cross walls and clamp connections typical of higher Basidiomycetes.Experiments showed that the dormant sclerotial mycelium must have undergone a period of adaptation before it grew in the artificial media.However

it took only within a week for the vegetative mycelium to cover the entire surface when transfered to an agar slant.In liquid culture

aeration ap- parently favored its growth

the maximun growth being obtained in about 12-20 days in still flask culture

in 5-7 days in oscillating flask culture and in about 3-5 days in aerated tank culture.The crude extract of liquid culture was found almost as effective in supress- ing the sarcoma 180 cells in the ascites of the test mice as those of the natural sclerotia of Polyporus umbellatus（Pers）Fr..