The clay mineral assemblages of the Sambesan loam and of the Daisen loam have been investigated on the basis of stratigraphic successions by mean of X-ray diffraction and of differential thermal analyses. The both loam beds are generally composed of four or more pumice layers and intercalated clayey layers. The clay minerals of the Sambesan loam and of the Daisen loam comprise mainly of 14Å minerals (chlorite, Al-vermiculite), 10Å minerals (illite, hydrated halloysite), 7Å minerals (kaoline minerals, chlorite), allophane and imogolite. The pumice layers are divided into three types, such as, I. allophane type, II. type which contains 14Å, 10Å and 7Å minerals and III. hydrated halloysite type. In general, the upper pumice layers are allophanic, however the hydrated halloysite are dominant in the lower pumice layers. The same tendency are also observable in the intercalated clayey layers which are characterized by the occurrences of various type clay minerals mentioned above. The results of differential thermal analyses for the samples from columnar sections support the same conclusion.

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In July of 1970, nearly complete, skeletons of a fossil elephant were excaveded from Quaternary sediments on the spot of construction at Bansei, Churui-mura Hokkaido. The elephant bearing bed is the peat bed in Bansei sand and gravel Formation. The writer could collected the many plant remains from the elephant bearing bed. They are 16 spcies belonging to 14 genera and 10 families, among them 2 species are not found in the present flora of Tokachi Plain. One of them is Fagus crenata Blume, and the other is Styrax japonicus Sieb. et Zucc.. They are growing in the temperate zone, in the southwestern part, southward from Kuromatsunai depression in Hokkaido. This fact indicates that Fagus crenata and Styrax japonicus had been in Tokachi Plain at time, may contribute to the Pleistocene paleobiogeography as one of the important data.

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Endops yanagisawai (Endo & Matsumoto) gen nov. 1) Dorsal shield oval. 2) Glabella urceolate, strongly expanded forward with a flat marginal border, granulose. 3) Occipital ring rather with tubercles stand in a line. 4) Preoccipital lobe small, length-ways elongate, trigonal. 5) Eyes large, reniform, half long as grabella. 6) Free check rim inflated or slightly rounded. 7) Genal spines short. 8) Thorax consists of ten segments. 9) Pygidium semicircular, axis composed of 8 to 9 segments, pleurae about 6 or 7 segments, rather, finely granulose.10) Occurs in the Yabeina zone of the Upper Permian, in G2 valley, Takakura-yama, northwest of Tamayama Mineral Spring, Yotsukura Town, Iwaki City, Fukushima Prefecture. Nipponaspis takaizumii Koizumi, gen. et sp. now. 1) Dorsal shield elongate oval. 2) Cephalon semicircular; geneal spine short. 3) Glabella lengthways elongate, narrow in the middle, widest at the posterior. 4) Lateral glabellar furrow in four pairs, shallow and short. 5) Frontal part of glabella without flat marginal border, but a narrow preglabellar field present. 6) Occipital ring rather wide with a tubercle. 7) Eyes very large, reniform, two thrids as glabella. 8) Genal spine short. 9) Thorax consists of 9 segments. 10) Pygidum semicircular, axis composed of 12 to 13 segments, pleurae composed of about 8 segments. Fringe of pygidium wide. 11) Occurs in the Yabeina zone G2 valley, Takakura-yama.

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Mg, Mn and Fe contents of biotites from the Cretaceous Hiroshima Granite are determined. The Cretaceous Hiroshima Granite is very homogeneous under the microscope. But, Mn/Mg and Mn/Fe ratios of biotite are various. Biotite in granite which was intruded into the palaeozoic formation rich in Mn-ore deposites has higher Mn/Mg (0.14-0.72) and Mn/Fe (0.024-0.052) ratios, on the other hand, biotite in granite which was intruded into the palaeozoic formation poor in Mn-ore has lower Mn/Mg (0.06-0.38) and Mn/Fe (0.013-0.030) ratios. This difference does not be attributed to the crystallization differentiation. There must be a interaction between the granitic magma and the palaeozoic formation. This interaction may not be negligible when we consider the Granite Problem.

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