抄録
The developments of callus and adventitious roots were studied in cuttings of epicotylic shoots of akamatu (Pinus densiflora) seedlings, and the new shoots of modoomatu (so-called natural hybrid of P. densiflora×P. Thunbergii). which have developed from decapitated epicotyls of one year old seedlings.
At first, callus develop from the cambium and the phloemoand then, from the cortex near the phloem, and from the pith. In callus, irregular xylem tissues, which are accompanied by-cambium and phloem to its outer surface, develop in connection with the newly formed xylem of the stem.
Roots appear at first as the protuberances of callus, and seem to be exogenous in their origin. More detailed developing processes should be examined.
