A new massive coral found in a Carboniferous limestone, together with a Stylidophyllum, several other rugose corals and a chaetetoid, of the Taisyaku limestone plateau in Tyugoku, suggests hexacorals in being characterized by its maeandroid corallum-a growth-habit never seen among rugose corals-with narrow corallites lacking proper wall, connected by confluent, distinctly trabecular septa which are apparently disposed radially, and provided with variably broad papillar columella surrounded by an incomplete cycle of pali or pali-like elements. Superficially it resembles such Palaeozoic corals as Aulina, Phillipsastraea, and Orionastraea, and, among recent hexacorals, certain forms of the Agaricidae, especially of the genus Pavona, though quite distinct from all of them in the details of its inner structure. A new generic and specific name, Pseudopavona taisyakuana is here proposed for this interesting fossil coral it is to be referable to a new famiiy Pseudopavoniidae.
In the present snort paper, the present writer reported the occurrence of Vicarya callora forma japonica SAGA (MS.) from the lower part of the Kadonosawa Series (Miocene) of Yuda, Kindaiti-mura, Ninohe-gun, Iwate Prefecture. So far as our present knowledge is concerned, this fossil locality is the northernmost limit of the occurrence of Vicarya in Japanese Islands.
This paper deals with the descriptions of some fossil involucres of Ostrya and Carpinus from the Miocene rocks of Hokkaidô and Tytisen. They are as follows: Ostrya japonica SARGENT oblongibracteata subsp. nov. from the Kunnui Series of Abura in Hokkaidô Carpinus erosa BLUME ellipticibracteata subsp. nov. from the Kunnui Series of Ahura in Hokkaidô Carpinus simplicibracteata sp. nov. from the Enniti Series of Tyôsen. Carpinus Kodairae-bracteata sp. nov. from the Engelhardtia Beds of Tyosen. Ostrya japonica oblongibracteara is the first fossil involucms of O. japonica-type found in Eastern Asia, though some fossil leaves under this name have been reported from several localities. It resembles closely that of the modern O. japonica now living in Japan, but differs slightly in its longer and oblong shape. Carpinus erosa ellipticibracteata is very close to the modern a erosa of Japan and China, but generally oblong and elliptical in outline. C. simplicibracteata is, as well as the preceding one, a type belonging to the morphic group of C. erosa, but its apical nature and the nervation is quite characteristic as shown in the figures. C. Kodairae-bracteata that has trilobate involucres is related essentially to the modern Japanese C. laxiflora BLUME and similar also to such exotic species as Chinese C. Londoniana and C. lanceolata, European C. betulus and C. grandis (fossil) and American C. caroliniana.
With the exception of 4 species of Caenestheria and 2 of Cyzicus occurring between the isotherms of N 10°C and 20°C in July and a species of Caenestheria farther north beyond the isotherm of 10°C, all of the living estherids are distributed between the Northern and Southern isotherms of 20°C in July and January respectively, but the number of species tends to decrease in regions that are warmer than 30°C in July. Furthermore, the fact that many species are crowded in the basins along the Donau, Nile and other rivers cannot be overlooked. It may therefore be concluded that a temperate climate (+20°C in Summer) in the continental basin is the optimum for the estherids. Among the seven genera of estherids, Caenestheria, Caenestheriella and Leptestheria are eurythermal and Eoleptestheria and Cyzicus stenothermal, the remainder being intermediate. When the four species of Caenestheria known from the Tundra region are morphically compared with 4 species of stenothermal Cyzicus and 4 species of Eohrtestheria, also stenothermal, living in the Hungarian besin, the climate of which is quite suitable for estherids, it is found that the estherids in such unsuitable climatic condition as in the Tundra are commonly diminutive in form, with smaller number of growth lines. The ornamentation between the growth lines is independent of climatic conditions but of value in attempting classification of this group as demonstrated in the joint paper by the senior author and HIIZITA. From these observations, it can easily be presumed that glaciation of the past in Central Asia must have offered a barrier to their distribution. In this connection it is noteworthy that 8 of the 14 species known in Eastern Asia belong to eurypic genera while stenopic genera are represented by only 2 species. Of Mesozoic Estherites in Koreo-Manchuria it is known that the large ones are most common in the Jehol fauna, the reverse being true in the case of the Daido fauna. In the Kyöngsang and Sungari faunas the size is mostly medium, growth lines being however, commonly more numerous in the Kyöngsang forms. This fact together with others on the palaeogeography and palaeoclimatology suggests that the climatic conditions were the optimum for Estherites in the Jehol period while it was most unfavourable in the Daido period.