Many characteristic inclusions which are some-what globular and more mafic than their host rocks are in the hornblende andesites from the Myoko volcanoes. They generally contain glass and are porous. Such inclusions are also found generally in the intermediate volcanic rocks, especially in the hornblende andesites from other volcanoes in Japan. In the Myoko volcanoes, they have been called cognate inclusion, and interpreted as fragments of the rocks crystallized at a earlier stage in the same "evolutional series" as the host rocks. Many inclusions are contained in the basalt, pyroxene andesite, and hornblende andesite of the Myoko-IVth stage. The inclusions in the basalt are undoubtedly accidental xenoliths, and those in the hornblende andesite have been called cognate inclusion by previous workers, and have the same features as mentioned above. As the result of the microscopic observation, a continuous transition in texture (Table 4, Plate I〜IV), mineral assemblage (Fig. 4), and features of minerals (Table 4, Fig. 3) is traced from the accidental xenoliths in the basalt (Nishikawadani lava) through the inclusions in the pyroxene andesite (Tsubame lava) to the so-called cognate inclusions in the hornblende andesite (Otagirigawa pyroclastic flow). Therefore, such inclusions in the hornblende andesite are considered to have been formed through the reaction of accidental xenoliths with magma. Many inclusions called cognate inclusions from other volcanoes may have also originated from accidental xenoliths, because their features are very similar to those of the Myoko volcanoes.

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The soluble protein and the carbohydrate part separated chemically from the decalcified residue, and the undecalcified powder samples treated with hydrogenperoxide and base have been examined by amino acid, infrared and X-ray analyses for exploring the composition and the conformation of protein in the chitin-protein complex constituting the phragmocone of the cuttlebone of Sepia esculenta. The results suggest the following. 1. The composition of the insoluble protein differs from that of so called conchiolin-protein in the molluscan external shells. 2. The infrared spectrum of the soluble protein shows the conformation of protein may be almost the α-helix or random coils from the amido I absorption. 3. The infrared spectrum of the carbohydrate part shows that of chitin, but the small amount of amino acids are detected in this part. 4. The mineral component is only aragonite, and other mineral has not been recognized. Spacing values of the treated samples is not so different with one of the untreated cuttlebone. 5. The composition of the small amount of amino acids detected in the undecalcified samples treated with hydrogen-peroxide and base resembles that of so called conchiolin-protein, however does not show the characteristic pattern of the aragonitic shells.

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Around the Ise Bay the uncertain Pleistocene deposits such as the Kentoyama, Karayama and Taketoyo Formations are scattered on the top of hilly land. They unconformably lie on the so-called Tokai Group, commonly show unfossiliferous gravelly and sandy facies in lithology and donot have any original depositional surfaces. In the northwestern and southern parts of Tsu City, the Kentoyama Formation unconformably lies on the Age Group and is overlied by the higher terrace deposits. Generally it shows the frequent lateral changes in lithologic faices. Partly it shows the channel structure and cuts down the underlying the Age Group. Precise lithologic correlation in this formation is unable in the present study. But it yields abundant well preserved plant fossils, such as corns, seeds, wood spines, leaves, pollen grains and spores. From the view point of the fossil occurrences, especially by means of the pollen analysis the Kentoyama Formation may be correlated to the upper part of the Osaka Group. And it deposited in near shore swamps, because of the abundant occurrences of Trapa spp., Ceratopyllum demersum, Potamogeton cristatus, Nuphar sp., Nelumbo sp., Sapium sebiferum and Paliulus nipponicus.

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The southern part of the Tanzawa massif, Central Japan, is characterized by the existence of crystalline schist peculiar to the Neogene (partly Oligocene) System, the so-called "Green-tuff". Though the geologic problems especially the origin of the crystalline schist in this region have been discussed up to the present by many researchers, this have been unfortunately based on no reliable geological map. For the first time, the detailed stratigraphical study of this region (about 60 Km2) was carried out by the present writers. The Tertiary System in the surveyed area consists largely of subaqueous lava flows and pyroclastics. It can be divided into the following three formations in ascending order: the Kurokura formation, Yozuku formation and the Hirayama formation. The Kurokura formation is composed of basaltic lava flows and hyaloclastites, accompanyied by finegrained basaltic to dacitic tuff. The schistosity parallel to the bedding plane is distinct in this formation. In the northernmost part of the surveyed area, the formation is intruded by the quartzdiorite masses which gave contact metamorphism to the former. Though the lowermost limit of the formation is not confirmed, its thickness is more than 2,500m. The Yozuku formation is mainly composed of fine to coarse-grained tuff with andesitic to dacitic composition. The lava flows are scarcely accompanied in the formation. The schistosity develops weakly in the lower horizon of this formation, and the contact metamorphism by the quartz-diorite masses is negligible. The formation is intruded by many dolerite sheets, the large ones of which are observed in the Omata-zawa velley. The formation is about 1,400 m in thickness. The Hirayama formation consists largely of basaltic pyroclastics in the lower part and of basaltic lava flows in the upper part, respectively. No schistosity can be observed in this formation. The formation is intruded by many complexes composed of porphyrite and quartz-diorite in the western area. It is more than 900 m in thickness, though the upper limit is not yet confirmed. These three formations are surperposed without any remarkable unconformity. The general strike of these formation is E-W, though they are distubed by the block faulting. Apparently, these formations are northerly dipping in the greater part of the surveyed area, but sedimentary structures such as graded bedding and sole mark suggest that the southern strata represent the upper horizen in the stratigraphic sequence. Therefore, the greater part of the strata dipping northerly show reverse sequence. In the surveyed area, there are conspicuous three fault system : the high angle reverse fault system which partially parallel to the bedding plane and two normal faults with NE-SW and NW-SE directions. Of those, the NE-SW fault system, is particularly remarkable, dividing the surveyed area into many strip of fault blocks of 0.5-1.5 Km in width. Small-scaled folds with E-W axis seem to be developed in the southern side of River Yozukugawa, but their real form could not be clarified in the present study. Moreover, the distribution and the rock facies of intrusive bodies were also described in this paper. Based on the facts clarified by the present survey, some important geological problems in the surveyed area were discussed. Some conclusive remarks are summarized as follows; 1) The initial volcanic activity in the "Greentuff" basin of the Tanzawa massif was basic one. This may be common in the southern Fossa-Magna region, from the data in the Koma-massif, the Takakusayama region and so on. The initial basic volcanism is distinct from the initial intermediate volcanism in the " Green-tuff" basin of the North-East Japan. 2) Another phase of basic volcanic activity accompanyed by the intrusive one was also distinguished in the later stage of subsidence. 3) There were distinguished two phases in acid plutonic

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