The frequent occurrence of silicified erect stumps or lying trunks (commonly called “Matsuiwa”) in the coal seams makes a particular feature of the coal fields (Palaeogene) which are developed in a wide-spread area of the northern part of Kyushu Island. In observing through a considerable number of specimens obtained from several important coal-fields, I found that all of them belong to one and the same species which should be considered as a new taxon of Taxodioxylon in a wide sense (Taxodioxylon matsuiwa Watari in Bot . Mag. Tokyo, 79. 165-173, 1966). On the other hand, the clastic sedimentary strata of the Palaeogene of this area also contain the fossil woods abundantly and result of observations on these woods makes us possible to suppose the existence of laxuariant flora rich in dicot trees under warm-temperate or subtropical climate. It may highly be possile to assume, under the mutual supports presented by these palaeobotanical evidences and many geological investigations, that Taxodioxylon matsuiwa ever consisted the pure and swampy forests resembling those of the moderen Taxodium or Glyptostrobus in the growing habit.