Gozaisyo-Takanuki District in Central Abukuma Plateau, Northeastern Japan (Fig., 1) is composed of various kinds of metamorphic and igneous rocks., The northeastern half of the area consists mainly of rather low-grade metamorphic rocks such as green schist, actinolite-green schist, phyllite, fine-grained biotite schist etc., while in the southwestern half, igneous rocks such as granites and quartz-diorites become predominent, being closely associated with high-grade metamorphic rocks which consist of amphibolite, gneissose amphibolite, biotite schist and gneiss (including injection-gneiss) etc., Namitaki, where the amphibolite dykes under consideration are found, is situated in the northern part of the district and is consisted of quartz-diorite and schistose biotite-granite, the latter intruding in the former., As seen in Figs., 2-3, the amphibolite dykes clearly cut the schistose granite and the quartz-diorite xenoliths in it., The directions of the elongation and schistosity of the amphibolite dykes are NW-SE, or NNW-SSE, and are fairly consistent with those of the schistosity of the granite and the arrangement of the quartz-diorite xenoliths., The dykes are grayish green, fine-grained rocks, with siight schistosity, and are mainly composed of plagioclase and hornblende, with small amounts of biotite and quartz (Fig., 4-5., )., Their volume percentages are shown in Table 1., Most of the plagioclases are small granular crystals, but sometimes they show more or less lath-shaped appearance., Judged from their refractive index, they belong generally to andesine-oligoclase, but occasianally have decomposed basic cores., Rarely large porphyritic plagioclases exist, some of which show polysynthetic twinning (Fig., 6-8., )., Hornblende occurs also as small granular crystals, with X-pale yellow, Y-light yellowish green, Z-green, and shows slight parallel orientation., They sometimes flock together, forming large spots which are often elongated in the direction of the schistosity., Biotite forms small flakes, with X-light yellow, Y=Z-yellowish brown to brown, and show parallel orientation, though irregular in distribution., Quartz appears in small-interstitial crystals, which are also irregularly distributed., Judging from their relict textures and mineralogical compositions, the original rocks of the amphibolite dykes might probably be the basic igneous rocks such as dolerites or diabases., After their intrusion into granite and quartz-diorite, they are amphibolitized and at the same time, slightly granitized by the regional metamorphism caused by the orogenetic movement and the concomitant invasion of granitic rocks, which took place probably in late-Palacozoic or early Mesozoic time., The frequent occurencc of ragged and mosaic plagioclases in the schistose granite and quartz-diorite shows that they were also subjected to the simultaneous metamorphism (Fig., 9-12., )., Accordingly we can distinguish the older and the younger granites in the present district., If we consider the granites without the metamorphic textures mentioned above to be the younger granites, most of the granites of this district belong to this group., Five years ago, Dr., K., SUGI suggested the existence of the older and the younger granites in the present district from the following facts: i) that the diaphthoritic rocks derived from high-grade metamorphic exist in the low-grade zone of this district., ii) that these diaphthorites again gradually raise their metamorphic grade., iii) that among them are found those which are considered to be derived from injection-gneisses., The conclusions drawn in the present papar, as to the granites of this district, are fairly agreeable with Dr., K., SUGI's suggestions mentioned above., If the younger granites of this district are late Palaeozoic or early Mesozoic as have been believed, the older granite must be of still more ancient date.,

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The Hidaka System of Hokkaido is a complex chiefly composed of sandstone, shale, chert, clay-slate, schalstein and limestone ; it is rarely fossiliferous., The fossils, hitherto reported to occur are bryozoas, brachiopods, a calcareous alga and a tabulata coral., Among the material from the provinces of Hidaka and Isikari now at hand, the writer could distinguish three different species of Batostomella and a calcareous alga, gen., et sp., indet ; besides there is one specimen of Chaetetes sp., in a limestone boulder from Kitami province., Batostomella sp., (1) is similar to B., columnaris (SCHLOTHEIM) of WAAGEN and WENTZEL from the Productus limestone of the Salt Range ; Batostomella sp., (3) is quite identical with the one from Hirabara in the Akiyosi district, where many bryozoas and tetracorals of Permian nature occur in association, and Batostomella sp., (2) though more or less problem-atical in its generic position distinctly exhibits characters of the Palaeozoic Trepostomata., The same calcareous alga as that found in this Batostomella limestone also occurs in a limestone of Nukata in Amata province, from where several other fossils of Permian nature are known., Chaetetes sp., is specifically indeterminable, however, it is in its internal characters quite identical with a species common in the Moscovian limestone from Japan Proper., On these fossil evidence, the Permian age of the Batostomella limestone and the Middle Carboniferous age of the Chaetetes limestone seem to be evident.,

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本化石はエクアドル國太平洋岸サンタ・エレナ半島, ラ・リベルター附近の崖に露出するデルタ堆積中の化石帶に發見さる。本化石帶の時代はPleistoceneに屬し, 筆者はβ化石帶と呼ぶ。化石帶の厚さ約50cm, アスファルトの存在により化石は茶褐色を帶ぶ。隨伴せる動物群は主として草原性にしてNeohippus・Protauchenia・Smilodon・Protolycalopex・Palaeospeothus・Palaeoodocoileus・Megathrium・Mylodon・數種の小型齧齒類・其他鰐・龜・多數の昆蟲・現棲種の鳥類・蛇・蛙等發見さる。化石は大臼齒を完全に有する左側下顎骨1個及び3個の分離せる下顎臼齒にしてCaviidae科の亞科Hydrochoerinaeに屬す。著者は本化石によりProhydrochoerus sirasakaeなる新屬新種を創れり。現生Hydrochoerus屬は水中及び濕地に棲息し, 短頭, 短躯四肢短し。齒隙は主顎に於て齒列より短し。Protohydrochoerus屬は草原性にして, 頭骨及び四肢長く, 齒隙は齒列より長し。Hydrochoerus及びProtohydrochoerusに於てはlamellaeに狹き連絡あるもProhydrochoerusは純然たるelasmodontなり。齒隙及び齒の構造より見てProhydrochoerusはHydrochoerus及びProtohydrochoerusの中間型なるべし。本稿をエクアドル・エスメラルダス州に於て調査に從事中不幸にも犠牲となりし故白坂虎吉技師の靈に捧ぐ

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We have no definite information as to the systematic position of the genus Macclintockia ; some species of the genus has usually been recognised as a representative of the Urticaceae or Myrtaceae on the ground of similarity in the leaves but one of the species, M., lyallii from Kobe, has great similarity to the leaves of Potamogeton franchetii, one of the species of Potamogetonaceae., From the geological occurrences it appears that the genus was widely distributed from the Cretaceous to the Miocene, but it was absent in East Asia in the upper Miocene age., The specimens, which were stored in the Institute of Geology and Palaeontology of the Tohoku Imperial University, Sendai, are as follows: I., Macclintockia trinervis HEER., Localities: 1., Tei, Maoka-mati, Karafuto., (Nisisyakutan formation)(Figure 1., ) 2., Honbetu, Mikasayama-mura, Sorati-gun, Hokkaido., (Poronai Series) 3., Horonitatibetu, Numata-mura, Uryu-gun, Hokkaido., (Poronai Series)(Fugure 2., ) 4., Yubari-mati, Yubari-gun, Hokkaido., (Poronai Series) 5., Otiai-ike, Suma-ku, Kobe, Honsyu., II., Macclintockia cfr., trinervis HEER., Locality : Konsyun, Manchoukuo., III., Macclintockia lyhllii HEER., Locality : Okuhata, Suma-ku, Kobe, Honsyu., IV., Macclintockia sachalinensis KRYSHTOFOVICH Locality : Tymovskaya Padj near Niklewicz's coal mine, North Saghalin.,

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