In the present article, the writer has attempted to give an account of a preliminary survey of the Pliocene Foraminifera from Japan., The materials examined are derived from many geographically isolated localities, and are classified into the following 18 faunal associations., (A) Foraminifera-Province of the Japan sea (Ura-Nippon) type., Of many different species of Foraminifera distinguished up to the present time from the Japanese Pliocene, some species are found to be short-lived and distributed only in the northern Japan (Ura-Nippon), and are not known from the Pacific side of Japan., These characteristic species are listed in Table 3., In the present province, 9 faunal associations are included., 1., Anden association., A study of Foraminifera collected from the Pliocene of the Oga Peninsula has led the writer to the recognition of three foraminiferal associations., Anden association comprises the fauna of the "Sibikawa" beds as defined by OHASI and TOYAMA., 2., Wakimoto association is for the Foraminifera fauna of the "Wakimoto" sandy shale defined by OHASI and TOYAMA., 3., Taya association comprises the fauna from the "Kitaura" beds as defined by OHASI and TOYAMA in Oga Peninsula and "Taya" beds of K., HATAI in Iwami-Sannai-mura, Kawabe-gun, Akita prefecture., 4., Setana association is divided into three subassociations-Kuromatunai, Hanaisi and Setana ; the faunule from the districts of Hanaisi and Setana, composed of several characteristic forms of the Cassidulinidae and Polymorphinidae, should be considered to mark the northern limits of the "Cassidulina province of the Japan Sea type", and may be correlated to the Wakimoto and Daisyaka associations, while that from Kuromatunai is related to both the Japan Sea and Pacific types, and may be comparable with the Anden association in Oga Peninsula or Naganuma association in the Miura Peninsura., 5., Daisyaka association is from a comparatively coarse grained sandstone exposed in the region of Utimanbegawa, Higasi-Turuga-gun, Aomori prefecture; the fauna seems to be closely related to that of Wakimoto association on one hand and that of the Onma or Natukawa on the other., 6., The materials of the Natukawa association are derived from Natukawadani and Simotaka-mati, Kitadyo-mura, Kariha-gun, Niigata prefecture, both belonging to the "Natukawa" beds as defined by OMURA and CHITANI., 7., Sawane association from the Pliocene of Sawane, Sado Island, may be correlated to the Natukawa association., 8., Tagawa association comprises the fauna of the "Tagawa" beds as defined by T., ONOYAMA., It may be slightly younger than the Natukawa or Onma which are widely distributed in the Provinces of Kaga, Noto, Etizen and Etigo, and should be correlated to that of Anden in Oga Peninsula., 9., Onma association is for the Foraminifera fauna of the "Onma" beds defined by T., ONOYAMA., It is closely related to that of Natukawa and also to those of Kakegawa in Sizuoka prefecture., (B) Foraminifera-Province of the Pacific (Omote-Nippon) type., The fossils of the Nodosariidae found in the Neogene of Japan mostly belong to recent species, but there are many forms not hitherto recorded from the surrounding seas., Of them, 18 species ; namely Robulus costatus (F., & M., ), R., costatus subdecoratus (CUSHMAN), R., costatus multicostus (CUSHMAN), R., abensis ASANO, R., papillosus (CUSHMAN), R., tumidus ASANO, R., surugaensis ASANO, R., calcarioides ASANO, R., bicostatus ASANO, Pianularia japonica (ASANO), P., kakegawaensis (ASANO), P., boso ASANO, P., yabei ASANO, Lenticulina kamakuraensis ASANO, Vaginulina boso ASANO, V., miuraensis ASANO, V., awaensis ASANO, V., tibaensis striata ASANO are distributed only in the Pliocene of the Pacific side and not known from the Japan Sea side. [the rest omitted]

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A peculiar formation was recently reported from Kamimasuki-gun, Kumamoto-ken, central Kyusyu by certain geologists working on Southwest Japan., And the present paper is a report of our preliminary study on it., The complex is here called provisionally the Mizukosi formation., It is a thick series of slaty shale with intercalating members of conglomerate and sandstone and containing lenses of limestone., It is noteworthy that the conglomerate contains iu abundance rounded pebbles, cobbles, and boulders of granite and altered green andesites or porphyrites ; and the material of sandstone is also grains derived mainly from similar igneous rocks., Through the study of fossils (see list in the Japanese text) found in the limestone, we have ascertained that the formation belongs to the upper Titibu system, i., e., the Permian., In conclusion, we have pointed out several geological problems related to the Mizukosi formation., Among them the question of Palaeozoic igneous aetivity in the Japanese Islands may be the most interesting.,

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本文は藤本治義博士が關本山地五日市附近深澤の侏羅紀鳥ノ巣石灰岩中より採集せしAcervulinaの記載である。Acervulinaは今日温暖なる淺海に極めて普通なる種屬で新第三紀層中にも夥多産する, 化石として最も古い者は白堊紀より知られて居るのみであるから今囘侏羅紀層から發見せられた事は特記に値する。鳥ノ巣石灰岩のAcervulinaは現生種Acervulina inhaerens SCHULTZEに類似するが垂直壁が著しく厚く, 房の輪廓が常に不規則でまた房の高さがAcervulina inhaerens の者の平均より低い。故に玄に本化石に對し Acervulina inhaerens huzzimotoiなる新變種名を提議する。

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鹿兒島市の北西2里乃至4里程の地域に發逹する含植物化石層から理學士山口鎌次氏が採集した稍〓多量の化石植物を同氏の好意によつて親しく拝見するの機會を得たが, 此植物群は種々の點から見て興味あるものであるから次に其梗概を述べたいと思ふ。さて材料の主なるものは鹿兒島縣鹿兒島郡吉田村五反田の南, 本名川河岸に露出して居る白色硅藻土質凝灰岩(2)から採集されたもので山口鎌次氏によると其層序は次の通りである。上方より列擧すれば 1., 浮石及び砂土 2., 白色硅藻土質凝灰岩(走向, 北70°東, 傾斜5°北) 3., 紫蘇輝石, 角閃石粗面岩質安山岩 4., 含玄武質安山岩, 集塊岩 又此他に別表(Table I)の産地から可なり多數の材料が採集された(Table I.,參照)。此含植物化石層なる硅藻土質凝灰岩を顯微鏡下に檢すると多數のCyclotella cfr., comta (EHRB.,) KUTZ, Cyclotella cfr., striata GRUM と少數の Epithemia cfr., hyndmannii W., SM., 及び Synedra sp., が認められた。是等は栃木縣鹽原温泉の更新世植物化石層及び宮城縣刈田郡圓田村の更新世と考へられる硅藻土の中に多量に包含せらるる硅藻と全く同一のものである。次に化石雙子葉植物の葉の印象を見るに標本全部で63箇の中40箇は實に Fagus crenata BLUME で其他には Carpinus laxiflora BLUME 1箇 Zelkowa serrata MAKINO 2箇 Aecr sp., (保存不良) 2箇 Quercus sp., (保存不良) 6箇 Salix sp., (保存不良) 3箇 Phyllites sp., (葉の破片) 7箇 Stem (印痕) 2箇 等が認められた。則ち保存良好なものの大部分(90%以上)が Fagus crenata BLUME であつて他は保存不良で種の同定困難なものが多い。用意周到なる山口教授が採集されたのであるから化石として保存されて居るものを注意深く持ち來たされた事は明らかである。夫れ故此化石植物の材料を供給した森林は恐らく Fagus crenata BLUME の純林であつたのではないかと思はれる。 Fagus crenata BLUME は KOPPEN の Climatic formula で現はすと Cfb (海岸で言ふと北海道函館附近)の氣候状況のところに最もよく繁茂するものであるのに是が鹿兒島灣岸に近き海面上, 高度50米乃至100米附近に其純林をなして居たと見られるのであるから我等の感興を引くことが大である。 Fagus crenata BLUME は現在九州南部に於ては其最低限界1000米であるとの事があるから今囘の發見は其地質時代の氣候を考察する上に重要な材料である。次に此植物群の地質時代を案ずるに, (1) 遠隔の地方に現生する要素を缺き, 悉く九州島に現生する種であること (2) 化石植物の産出場所よりも北方に分布する現生種を有すること。 (3) 化石植物の産出場所に於ける地質時代の気候状況が現在のそれより遙かに寒冷であつたこと等から考察して此化石植物群は第三紀のものでなく第四紀更新世の或時期のものなる事は確實である。則ち此材料は日本更新世の或時期に於て Fagus crenata BLUME が鹿兒島灣岸に近く夥しく繁茂した證據と見るべき重要な材料である。なほ日本群島産Fagus crenata の化石は別表(Table II)に示した如く多數發見されて居るが今囘の材料は櫻島産のものと共に其最南端のものである。

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