A palynological study was made on the Holocene sediments of two sites in south western Japan, Ukishima-no-mori moor, Shingu City, Wakayama Prefecture, and the Mutotsu River, Muroto City, Kochi Prefecture. At Ukishima-no-mori moor, the pollen diagram was divisible into three local fossil pollen assemblage zones, (1) the Quercus (Lepidobalanus)-Carpinus zone, (2) the Castanopsis-Quercus (Cyclobalanopsis) zone, and (3) the Cryptomeria-Pinus zone. It was estimated that broad-leaved deciduous forest had changed into lucidophyllous forest prior to the KAh ash fall which occurred about 6,300 years ago and that lucidophyllous forest, especially Castanopsis-type, would be dominant around this moor. This transitional age preceeded that occurring in Central south western Japan. At the Murotsu River, it seemed that the Castanopsis forest, which was accompanied by Podocarpus and Myrica spp., reached its climax phase about 8,500 years ago. These findings may be explained by the fact that in the early Holocene, the surveyed areas were situated on the Pacific coast and had been influenced by the warm Kuroshio current.

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日本列島太平洋岸における完新世 (後氷期) の照葉樹林の発達史について, 各地で報告されている花粉分析結果を検討し, 主に黒潮との関連で考察した. 房総半島以南の太平洋沿岸地域では, 完新世の初期から照葉樹林が成立し, なかでもシイ林の発達が顕著にみられた. とくに伊豆半島や房総半島南端で照葉樹林の発達が良く, その成立, 拡大時期も早かった. これらの地域は早くから黒潮の影響を受け, 冬季温暖かつ湿潤であるといった海洋気候が照葉樹林の発達をより促したと考えられる. 照葉樹林は, 急激な温暖化とともに九州南端から日本列島を北上したが, 一方で黒潮の影響を受ける沿海暖地からもその分布を拡大していったことが推定された. また太平洋沿岸地域における照葉樹林は, 完新世初期に3回の拡大期をもって発達した.

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Using digital images of sand grain with a scanner, the training data set on minerals; quartz, feldspar, shale silicified stone and chart was made. The data set could be divided into five regions using the CIEL*a*b* color space methods. Especially color brightness and satulation are important to identity mienrals. Shapes of quartzs and feldspars are more rounder than other minerals. Filed observations were carruied out in Awaji Island and 17 samples of beach sand and 51 river were colleceted. The optimiation method was applied to estimate the impact rate from rivers toward beaches with a distance among a beach and a river. The estimated results are corresponding to the existing knowledge.

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The distribution of two sympatric crabs of the genus Plychognathus, P. ishii and P. capillidigitatus, occurring estuarine environments in Kochi Prefecture was studied from December 2004 to October 2005. Previously known localities for P. ishii and P. capillidigitatus in Kochi Prefecture were 12 and five, respectively. This study confirmed 18 and 12 new localities for each species. These two crabs were common in estuarine environments from central to western Kochi Prefecture. Their occurrence could not be confirmed in rivers where its mouth frequently closed by wave actions, and in rivers where its bed and banks protected artificially.

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The Nojima Earthquake Fault 18km long appeared along the northwestern coastal line in Awaji Island in the 1995 Southern Hyogo Prefecture Earthquake. This fault can be divided into four segments based on the morphological characteristics, geological structures, gravity anomaly, and distributions of aftershocks. These segments are named here from north to south, Nojima segment (Awajicho to Nojima river), Ogura segment (Nojima river to Toshima river), Ikuha segment (Toshima river to Murotsu), and Kareki segment (Murotsu to Ozaki). These fault segments form a dextral strike-slip fault system showing an en echelon form and generally trend toward N30°-60°E. The Nojima and Ogura segments coinside with the Nojima geological fault. The Ikuha and Kareki segments appeared as new fault ruptures, the former following almostly along the axis of the Mitsukoshi flexure, and the latter parallel to and partly along the Shizuki geological fault.
The boundaries between two adjacent fault segments along the Nojima Earthquake Fault are geological and geomorphological boudaries between the basement of Pre-Neogene granitic rocks and the Kobe Group and Quaternary deposits, and between the basin and hill. These boundries show the characters of dilational jogs. Furthermore, it is clear that the aftershock distributions are concentrated in the areas around these dilational jogs. It seems that the main earthquake rupture propagated southwestward from the main epicenter along the Nojima geological fault and then jumped to the next en echelon segment at the dilational jog to the southwestern end area.
As stated above, it is clear that the morphological distributions of the four fault segments of the Nojima Earthquake Fault are controlled by the deep geological structures. The topography and morphology of the Nojima Earthquake Fault provides both useful information on the mechanics of faulting and predictions regarding the heterogeneity of earthquake.

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土佐湾にそった平野部の花粉分析資料を中心にして, 南四国の第四紀初頭からの森林植生の変遷を概観した. 更新世全体をみると, Abies, Pinus, Picea, Cryptomeria, Tsuga などの針葉樹と, Fagus, Quercus, Betula, Carpinus, Zelkova などの落葉広葉樹が優勢で, 現在よりもかなり冷涼な気候であったと思われる. しかし更新世前期には, Keteleeria, Nyssa, Carya, Liquidambar, Taxodiaceae (Cryptomeria をのぞく) などの第三紀要素の植物が残存していた. また間氷期には, Cyclobalanopsis, Castanopsis, Myrica, Podocarpus などの暖温帯性の植物も生育していた. ただこれらの植物群が, 更新世を通してどのような盛衰をたどってきたかということは今のところよくわからない. 最終氷期の晩氷期から後氷期初頭にかけては, 冷温帯的な森林が海岸平野にまで広がっていた. 完新世中期の温暖期には, 冷温帯林は消滅し, 代わって暖温帯林 (照葉樹林) が拡大する. 完新世後期には気候の冷涼化とともに暖温帯林がやや減少し, 人間の活動が植生にあたえた影響も顕著になってくる.

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Although bone metastasis of a malignant tumor is not rare, it is generally thought that intraoral maxillary metastasis from other organs is rare.
The authors experienced a case of mandibular metastasis of the renal cancer, on which a report is made here with literature consideration thereof.
Patient: S.S. 49-year-old man (office man)
Initial medical examination: November 24, 1981
Chief complaint: Formation of a painless tumor at his left mandibular mental foramen region
Family history: Pneumonia (20 years ago) and sciatica (12 years ago)
Present illness: About a month ago, a thumb-sized swelling was noticed at his left cheek, and he consulted a town doctor for lower lip paresthesia. Chemotherapy was performed for 10 days without symptomatic improvement and he came to our Department of Oral Surgery.
Present examination: The patient had moderate general physique and eutrophia. His countenance was nearly symmetrical, however, a thumb-sized elastic and hard tumor was palpable at his left mental foramen region. On the affected side intraorally, there observed a defect of the mandibular molar and a tumor at the dental root of the mandibular premolar. There was neither gingival inflammation nor swelling of its attached submandibular lymph node.
Results of clinical examinations: X-ray exploration revealed a thumb-sized and comparatively well-defined bone resorption shadow, centering around his left mental foramen region. There were no abnormal values obtained from general blood examinations.
Treatment: The tumor suspected of mandibular cyst was extirpated under general anesthesia.
Results of histopathological examination: The extirpated multinodular solid tumor, covered with connective tissues, was diagnosed pathologically as a clear cell carcinoma with a honeycomb-like structure which was delimited by the abundant strome and blood vessels.
Postoperatively, the intraoral wound showed good healing, process however, the lung or kidney was suspected as the primary site of this tumor, and a co-exploration by the Department of Surgery and the Department of Urology and a detailed examination detected left renal cancer of the patient who was then transferred to be radically operated for renal cancer.
Literature examination of such cases revealed that intraoral bone metastasis of renal cancer was rare. The treatment of intraoral metastatic cancer is usually perfomed at its relatively early phase and its prognosis was frequency poor depending on the result of the treatment for its primary focus.

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　淡路島の諸海岸の砂の起源を特定するために，島内の18の海浜砂とそれに関係すると予想される河川の河川砂を採集した．筆者が前報で提案した砂の色による分析方法を適用するとともに，砂粒子の形状特性を分析した．加えて，各河川の流域地質特性を把握することによって，砂の色の成立要因について考察した．河川砂の色は，地質条件によって大きく異なり，火成岩地質を擁する北部地域においては黒系統で淡い色を，大阪層群優勢の流域では淡い茶色系統の色を，南部の和泉層群を擁する地域においては暗い色を有することがわかった．海浜砂の色は，河川砂ほど明確な色の差異はなく，これは風化，養浜，海浜間の砂の移動等が影響していると考えられる．

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The behavior of a PN-photodiode and its dependence upon the biasing electric field are discussed theoretically by taking into consideration the hot electron mobility and the space charge effect in semiconductors. It is shown that the non-saturation photocurrent is directly proportional to the reverse bias field in the depletion-layer of the linear-graded junction diode. These theoretical results agree with our experimental results which were obtained using a ruby laser as the optical source. The photocurrent, reduction factors and transit phases, the latter two of which are a measure of the frequency response, are obtained in the case where light is incident parallel to the junction plane and the electric field is distributing parabolically in the depletion-layer. It is shown from this analysis that the parabolic field distribution gives smoother reduction profiles than a uniform field. The relation between the laser intensity and the optimum biasing electric field is given.

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In the case of the sandy coast of the Hibikinada, the west end of the mainland, I explicate in this report the process of the formation of bars and sand dunes mainly from the Archaeolo-geographic point of view.
1. The purposes of this report are as follows:
To correct the formative period of the diluvial old sand dunes.
To discover the bars formed by the Jomon transgression.
To add the data to infer the existence of little transgression of the middle of Yayoi age.
2. There are two pleistocene coastal sand dunes, one was formed before the Göttweiger interstadial. The other is Ayaragi old sand dune, which was before the Paudolf interstadial.
3. In Holocene bars piled at the transgressions of the earliest Jomon, the early Jomon, the first half of late Jomon, the middle Yayoi and the incipient stage of Heian age, and then exposed by each later regression.
Sand dunes were formed four times in Holocene; in the end of the earliest Jomon, in the second half of the late Jomon, from the end of the medieval ages to the middle of the modern ages and in the present age.
The first beach ridge was formed in the earliest Jomon, the second in the first half of late Jomon and the third in the incipient stage of Heian age. The new sand dune which give the topographical change is Tomito new sand dune, which was formed from the end of the medieval ages to the middle of the modern ages.

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室戸半島大野台（134°00´E, 33°26´N, 海抜高度40–50m）の海成段丘面下堆積物に含まれる花粉および大型植物化石群から，暖温帯に分布するマツ属，モミ，ツガ，トガサワラなどの針葉樹とクマシデ属，ケヤキ，ブナ属，ナラ類などの落葉広葉樹からなる森林が復元された。この堆積物は，イオウを含有することと，ハマゴウなどの海浜植物の化石が産出することから海成とみなされ，段丘面高度分布と古地磁気層序対比から大阪層群のMa5海成粘土層の可能性が考えられた。同地域の完新世堆積物中の花粉群から復元される植生は常緑広葉樹林であったが，この堆積物が堆積した時代には，同じ間氷期でもシイ属，カシ類などの分布拡大がみられなかった。これは，常緑広葉樹林の成立を制限する冬の寒さなどの条件が間氷期によって異なっていたためと考えられる。

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大阪湾夢洲沖コアを用いた花粉分析に基づいて，完新世の大阪湾集水域における植生変遷を復元した．このコアからは多数の放射性炭素年代が得られており，11,100～9,800 cal BPではコナラ亜属やクマシデ属から構成される冷温帯性落葉広葉樹林が発達していた．9,800～9,000 cal BPでは，エノキ-ムクノキ林が拡大し，冷温帯性落葉広葉樹林はやや衰退した．9,000～5,400 cal BPでは，エノキ-ムクノキ林と冷温帯性落葉広葉樹林がアカガシ亜属やシイ属から構成される照葉樹林と交代した．5,400～2,900 cal BPでは，照葉樹林が最も発達した．2,900～1,200 cal BPでは，温帯性針葉樹林が増加し，照葉樹林がやや衰退した．1,200～300 cal BPでは，二次林であるアカマツ林が拡大し，自然林である温帯性針葉樹林や照葉樹林が徐々に減少した．また，緩やかな森林の減少が推測された．300 cal BP～現在では，自然林が急速に減少し，アカマツの疎林やはげ山が拡大した．

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プレート境界に沿って発生する巨大地震に伴う隆起地域として知られる室戸半島において,石灰質遺骸,海成段丘,離水波食地形を指標として,完新世における海水準の復元を試みた.これらの旧海水準指標は,垂直的に数10cm～数mの間隔を持った間欠的な分布を示し,I～VIの6つの旧海水準(レベル)が識別された.各レベルに対応する旧海水準指標は,¹⁴C年代から,それぞれ1:6,000～5,000y.B.P,,II:4,000～2,700y.B.P., III:2,600～2,200y. B. P., IV:2,000～1,100y.B.P.,V:1,000～800y.B.P., IV:700～200yB.P.に形成されたことが判った.認められた海水準の不連続的変化から,間欠的な地震隆起 (event 6～event 1)の存在を推定し,各eventについて隆起量の分布を復元したところ,内陸活断層の変位と重合した複雑なパターンを示す場合があることが明らかになった.本地域では,室戸岬における1回の地震による残留隆起量が0.2～0.3m程度の南海道地震(1946年,M=8.1)タイプの地震隆起が累積するような地殻変動が推定されてきたが,完新世においてはそのような地震隆起の累積はみられず,地震1回の残留隆起量がより大きな(最大数m)地震変位の累積が認められた.

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室戸岬地域の前期中新世四十寺山層は，日沖メランジュの上に堆積した海溝斜面堆積物と推定される．四十寺山層下部の泥岩は，枕状溶岩や火山角礫岩，火山性砂岩を挟在し，四十寺山ドレライトを含む．日沖メランジュには丸山ドレライトが貫入する．枕状玄武岩，火山角礫岩中の玄武岩質安山岩礫・ドレライト礫，丸山・四十寺山ドレライトは，非アルカリ岩系の玄武岩－安山岩に分類される．微量元素組成と単斜輝石組成を用いた判別図において，丸山ドレライトとドレライト礫はMORBに，枕状玄武岩や玄武岩質安山岩礫（椎名火山岩類），四十寺山ドレライトは島弧玄武岩に判別される．沈み込んだ四国海盆の活動的海嶺から付加体にマグマが直接供給されてドレライトの多くが形成された．椎名火山岩類の形成は，MORBマグマによる四万十泥岩の同化作用と分別結晶作用に由来する．ドレライトと椎名火山岩類は，海嶺の沈み込みに関連した海溝近傍火成活動の産物である．

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土佐湾北東岸に発達する海鍛丘は,上位より羽根岬面,室戸岬面および沖鷲地に分け皇れ,いずれも南東より北西に低くなる.室戸岬面の高さは南海地震の際の隆起量と正の相関を不し,地震削の沈降量とは負の相関を示す.約120年を周期としておこった大地震の際の室戸岬付近の隆起は,その間の沈降よりも大きく,段丘面の高度分布はこのような隆起沈降を差引した結果である南東より北西への傾動陸起にキって決定されたと考えられる.このような隆起地域であるにもかかわらず,各段丘面の形成過程に沈水期が挾まれているのは,氷期後の海面上昇速度が地盤の隆起速度を上回ったからに他ならない.
室戸岬面は,その地形発達の過程より判断して,約9万年前にはじまる. Riss- Würm問氷期に形成されたと考えられる.室戸岬付近の大地震1周期の問における地盤隆起の平均速度は約2mm/年と算定され,もしRiss-Würm問氷期以後かかる性質の地殼変動が一様に継続したとすれば,室戸岬面は室戸岬付近において約180mの高さにあるはずであるが,これは事実と一致する.また水準測量の結果によると,安田の水準点を基準とした吉良川の水準点の高度は,大地震1周期の問に平均1.2mm/年の割含で増大しているが,もしRiss.Würm間氷期以後このような地殼変動がつづV・てきたのであれば,室戸岬面は吉良川において安田よりも細10m高いはずであるが,これも事実とほぼ一致する.したがって, Riss-Würm間糊以後,室戸岬付近は現在と同じく平均2mm/年の速さで北西へ傾動しつつ隆起してきたと考えられる.
このような地殼変動と第四紀における海面変化とを複合した結果は,この海岸の地形発達の過程とよく一致するので,この地域の海岸段丘の分化を生じたのは,地殻変動の緩急ではなく・海面変化の結果であり,その間地殼変動はほぼ一様に推移したと考えられる.

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