1.The base of the branches of Bladhia Sieboldii is widened and the branches disarticulate from their very base leaving scars on the axis. In such a base, the vascular ring of the branch widens extremely, so that the branch base is feeble mechanically. 2. Through the weakness or death of the branch, a cleft is formed at the base merely due to the separation of cells. Then the cells of the cleft elongate and next the formation of a cork layer is commenced. 3.Bladhia humilis, B. lentiginosaand B. cornudentata show the same construction of the branch system as B. Sieboldii. 4.Bladhia japonica, B. montana and B. crispa are distinguished from the species above stated in the rarity of branching and absence of cortical bundles. Even when the branch is found, its base is not widened and no characteristic widening of the vascular bundle is found. 5.The construction of branch base and the mechanism of disarticulation of the branch of Bladhia are different from those so far known of.