The nucleus-like body was found in the fossil seed wing of Picea mkximowiczii collected from the Plio-Pleistocene Osaka Group. The brief description of the nucleus-like body is as follows. One cell in the fossil wing has one nucleus-like body of which color is dark brown. Each nucleus-like body in cells is about 0.01 mm in diameter. The shapes of nucleus-like bodies are classified into two types, that is, one is circular and the other is semicircular.Especially, it is remarkable that all of the nucleus-like bodies of semicircular type attach to the cell wall. Observing the nuclei in cells of the wing of the Genus Picea living now they show the same morphological characters as the nucleus-like body descripted above. For example the semicircular nuclei are also observed in the cells of the rather adult wing of Picea glauca and all of the them attach to the cell wall, as in the case of the nucleus-like body of fossil wing. Judging from the fact that the nucleus-like body has some features common with nucleus of recent sample, it is highly probable that the nucleus-like body originated from nucleus.

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Fissures caused by Matsushiro earthquake in 1965 are divided into two types. One is creeping landslides, and the other is connected with the fault. The former is visible in the following areas: Nuruyu in Wakaho town, Nagai and Nagare in Matsushiro town Nagano City and Kuiishi, Kosnoku City. Intervals of the above area all in 8-10 km. The line linking these areas running with the direction of NNE-SSW, nearly parallel with the one of tectonic line in these areas. And it also coincides with the one of the long axis of the oval form, evolving epicenter's distribution. The latter is found in the areas such as Hannyaji, Takehara and Sezeki in Matsumoto town. The number of fissures in each area is several, following closely after with the direction of EW. They run in a zone of the direction of N60W, whose width is 200 m and length is 2.4 km. It is supposed that this zone is a stress one suffered pressure with a direction of EW. Considdering from the existence of left lateral sliding fissures, the writer suposed that the stress zone were made by the same movement of dormant fault. The direction of it coincides with the sort axis of clipsoid area of epicenter's distribution. These two directions of fissures almost harmonize with the main lectonic direction prevailing in the northern Fossa Magna.

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From the analysis of molluscan assemblages found in numerous shell mounds, the following conclusions are drawn as to the sea conditions around Hokkaido in Post-Glacial Epoch. In the late Earliest to the middle Early Jomon cultural age (Ca. 5,000-6,000 years B.P.) such warm sea molluscs Rapana thomasiana, Meretrix lusoria Mactra veneriformis were widely distributed along the coast line of Hokkaido. Therefore, it is assumed that the surface temperature of the sea around Hokkaido at that time must have been 8℃ at the minimum, and 23℃ or more at the maximum. Then the sea level reached the maximum height of 3 m± resulting the so-called Jomon Trangression. From the late Early to the middle Middle Jomon cultural age (Ca. 4,000-5,000 years B.P.) the molluscan assemblages in various shell mounds reveal discrepancy between the Japan sea side of the island. On the Japan sea side, molluscan elements were similar to those of the preceding age. While on the Paific side the dominance of cold water elements became notable. Judged from this evidence, the sea temperature might have remained more or less the same with that of the preceding age on the Japan sea side, where as it might have been colder than before on the Pacific side, though it still was definitely higher than the present day sea temperature of the same region. As to the height of sea level of this age we have not sufficient data to confirm, but it was presumably a little lower than that of the preceding age. From the late middle, or the Late Jomon cultural age onward the molluscan assemblages became essentially the same reflecting the present distribution of molluscs in Hokkaido, where the sea conditions also became similar to those of the present.

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[in Japanese]

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