Abstract
This paper deals with the "lysigenous intercellular space" in the culm, its distribution and process of development and its ecological and specific variations in rice and other graminaceous plants. As one of the ventilating systems in the internode of the rice plant, we can recognize aerenchyma in the lower unelongated internodes and "Lysigenous Intercellular Space" in the elongated ones. The lysigenons intercellular spaces in the culm and sheath are connected anatomically through the aerenchyma of the node with each other and also with the cortex of the root tissues. The development of the lysigenous intercellular spaces in the rice culm are affected by the environmental conditions. They develope rather better under excessively moist or "akiochi" -O2 lacking- conditions. It was found that, of gramineae, the lysigenous intercellular spaces in the culm of the speces particularly adapted to moist or excessively moist conditions were generally larger than those in the species adapted to dry or semi-dry conditions and that they develop more extensively according to the moistness of growing environments.
