Proboscidean Research Group is making systematic and synthetic studies of the elephant molar teeth from the microscopic to macroscopic level. In this paper the author made scanning electron microscopic observations of molars of four elephant species; Elephas indicus (Elephas miximus), Loxodonta africanus (Elephas africanus), Elephas namadicus naumanni MAKIYAMA (Elephas naumanni MAKIYAMA) and Elephas primigenius (Mammuthus primigenius). Each specimen is polished along three axes of the molar. The enamel was divided into three layers: first, middle and deep. The middle layer was where Shreger bands were observed. At the horizontal section of the molar, most of the enamel of the middle layer revealed a "frond of the maiden hair fern" pattern, as pointed out by MUMMERY (1924). From this observation, it was deduced that this prism pattern was common in three species of Elephas out of the four (except Loxodonta africanus). At other layers, the first and deep, a few other patterns were also observed. In the dentine of fossil elephants, on the other hand, fibrillar structures which were similar to the collagen were observed with electron microscope. This problem should be more thoroughly investigated in order to understand the calcification process of the animal on a ultrastructure level.

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In this report, the authors have dealt with the stratigraphy, litho-facies, and geological structure of the Palaeozoic formations, that are distributed in the northern part of Kyoto City, which is located at the eastern part of the district described in Part II. The sequence of the Palaeozoic formations is as follows (in descending order): The Ohmori The Kumogahata synclinal area synclinal area l. Sandstone formation 1750 m 1750 m k. Chert formation 210m 1200m j. Shale-sandstone formation 1000m 4000 m + i. Chert formation 800-250 m 600-400 m h. Schalestein formation 50-300 m 100 m g. Shale-sandstone formation 1500 m + The thickness of the entire formations measured in this district attains to 5310-4800 m at the Ohmori synclinal area and to 7650-7450 ra at the Kumogahata synclinal area. Some fusulinids fossils, namely Pseudoschwagerina sp. and Pseudofusulina sp., were collected from a few limestone-lentils in the f-schalestein formation. So the greater part of the formations in this district is regarded to be Lower to Middle Permian in age. The formations form as a whole a synclinal structure named "Shuzan syncline" by MATSUSHITA (1953). It has been cleared that the syncline was composed of two minor synclines plunging to the west and to the north-west and an anticline also plunging to the west. The thickness of clastic formations obviously increases four to ten times from the wings of minor synclines towards their axial parts. The variation in thickness is related to the original amounts of sediments. We have also referred to the sedimentary features of some bedded cherts collected from the surveyed area.

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