The authors collected small mammals on Mt. Daisen in south-west Honshu and the Oki Islands. The Oki Islands lie in the Japan Sea about 80km off the northern coast of south-west Honshu, the main island of Japan. The Oki Islands consist of Dôgo Island and Dôzen Islands. Dôgo Island, the largest of the Oki Islands, have an area of 246km². Dôzen Islands are the general name for the group of islands which are situated at some distance from Dôgo.
The vegetation of Oki Islands, apparently the laurilignosa climax, consisted chiefly of Cyclobalanopsis and Machilus. The vegetation of the montane zone (alt. 800-1600m) of Mt. Daisen in south-west Honshu has the appearance of decidous forest the climax, consisting of Fagus.
Total number captured was 196 with the following proportional breakdown:
On Dôgo Island (420 traps-nights)
Apodemus speciosus navigator _??_23, _??_30
Apodemus argenteus celatus _??_1, _??_4
Eothenomys smithi okiensis _??_2
Urotrichus talpoides minutus _??_10, _??_25
On Dôzen Islands (160 trap-nights)
Apodemus speciosus navigator _??_6, _??_14
Apodemus argenteus celatus _??_1, _??_2
Urotrichus talpoides minutus _??_1, _??_3
On Mt. Daisen (montane zone) (260 trap-nights)
Apodemus speciosus speciosus _??_19, _??_8, unknown 1
Apodemus argenteus argenteus _??_10, _??_11
Eothenomys srnithi smithi _??_5, _??_3, unknown 1
Urotrichus talpoides hondonis _??_8, _??_8
Body size, testicle size, and embryo size of each species are shown in Tables 1-8. We compared the island forms with the main land forms and the following tendencies were noted.
1) Coloration of back and abdomen is blackish in island forms of Apodemus speciosus, A. argenteus and Eothenomys srnithi.
2) Body sizes of island forms of Apodemus speciosus are larger than the main land form. In the Dôzen Islands form especially, the hind foot length is conspicuously larger than both main land and Dôgo Island forms.

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The western offshore area of the Oki Islands is evaluated as one of promising area for oil and gas exploration, because of the thick accumulation of sedimentary rock based on the results of seismic surveys. To establish the chronostratigraphic framework with high resolution in the area, the biostratigraphic study of fossil diatoms was carried out for the samples collected from the Miocene Kumi and Tsuma Formations mainly exposed in the national park in Dogo, Oki Islands, Shimane Prefecture.

The Crucidenticula kanayae Zone (16.6 - 17.0 Ma) was recognized from the samples about 10 m above the lowermost lacustrine Kumi Formation in the Kumi River, which indicates that the geologic evidence of the first marine invasion related to the Japan Sea spreading was recorded in the northern part of Dogo. The Zone including the biohorizon D33, the last occurrence of C. kanayae (16.7 Ma), was found in the Nogoshi section exposed in the northwestern part of the island. The stratigraphic change of diatom assemblage suggests a gentle transgressive trend through the C. kanayae Zone. The specimens of C. kanayae yielded from the Kumi Formation are identified as C. kanayae var. kanayae showing a wide range of morphological variation. The shallow marine sandstone is expected to be a good reservoir rock distributed in the lowstand systems tract correlated with the layer just above the C. kanayae zone.

The Crucidenticula nicobarica, Denticulopsis praedimorpha and Denticulopsis dimorpha Zones were recognized from the Kumi Formation in an about 10 m thick section in the Nagu Peninsula area of the southwestern part of the island. This suggests a condensed sequence developed from late Middle to early Late Miocene in the area. The sequence which is correlative with the black mudstone, the Utagi Mudstone Member, seems to have the highest source rock potential in the area. The lower Neodenticula kamtschatica Zone was recognized from the Igo Mudstone Member along the Nakanoura shore of the northern part of the Island. The Tsuma Formation showing lateral lithofacies changes in Dogo indicates low possibility of the cap rock existence for the unconformity play of the uppermost Kumi Formation.

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A biostratigraphic study of fossil diatoms revealed that the most of the Kumi Formation in Dogo, Oki Islands, is correlative with the Crucidenticula kanayae Zone to Thalassiosira yabei Zone, and that the Tsuma Formation with the Rouxia californica Zone to lower Neodenticula kamtschatica Zone, respectively. On the other hand, the lowermost of the Kumi Formation yielded a Lower Miocene freshwater planktonic diatom assemblage. The assemblage mainly consists of various forms of the genus Auracoseira associated with lacustrine Actinocyclus species. It is overlain by the marine Kumi Formation correlated to, or lower than, the Lower Miocene Crucidenticula kanayae Zone (16.6-17.0 Ma) which evidences that the geologic section recorded the first marine water invasion related to the Japan Sea opening in the area. This abrupt change of the diatom assemblage from freshwater to marine planktons suggests the rapid transgression in the area where wide continental shelf did not develop. In addition, this study shows the first discovery of the biostratigraphic index diatom fossil N. kamtschatica from the Tsuma Formation which is the westernmost occurrence from the Japan Sea side.

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Recently, many functional areas have been identified in the parietal cortex of the brain in monkeys, and owing to this, cytoarchitectonic subdivision has been elaborated in the monkey parietal cortex. This review deals with sulcal patterns of the parietal lobe in human and monkey brains, and corticocortical connections of both neurophysiologi-cally defined regions and cytoarchitectonic areas of the parietal cortex in monkeys. The author proposes that the transverse occipital sulcus is a boundary between the parietal and occipital cortices in the human brain. A brain map of the monkey is presented. The parietal cortical areas are subdivided into somatosensory, eye movement related, hand or upper limb movement related, vestibular, and auditory areas, according to neu-rophysiologically defined functions of individual cortical areas. The somatosensory system contains areas 3a, 3b, 1, 2, 5, 7b, and SII: S1 projects to motor and premotor areas and somatosensory association areas project to premotor areas, the prefrontal, temporal, and limbic cortices, and the hippocampus. The eye movement system is composed of areas 7a, LIP, and PIP: It receives input from visual and temporal cortices and sends output to premotor areas, the prefrontal cortex, and the hippocampus. Hand movements are mediated in areas AIP, VIP, CIP, MIP, PEc, and V6A: These areas receive afferents from somatosensory areas, visual and temporal cortices and send efferents to the ventral premotor area. The vestibular functions are executed by coordination of areas 3aNV, 3aHV, 2NV, Ri, and VPS: These areas reciprocate with the cingulate cortex and insula and project to the ventral premotor area, SWA, and frontal eye field. The auditory system involves areas VIP and LIP: It receives afferents from the superior temporal sulcal cortex and sends efferents to the premotor area, frontal eye field, and prefrontal cortex.

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本研究では，隠岐

（どうご）の森林渓流水質の特性を明らかにするため，隠岐の森林渓流81ヶ所の渓流水質を調べ，採水地の集水域の地形および植生との関連を考察した。隠岐の森林渓流水では，日本全国の平均的な森林渓流水に比べ，4.9倍のCl^－濃度が観測された。また，電気伝導度およびNa^＋，K^＋，Mg^2＋の濃度についても大きな値を示した。これらのイオンの全国平均との濃度差におけるCl^－との比は，海水における元素比に近いことから，海塩の影響が強いことが考えられた。HCO₃^－は，Mg^2＋およびCa^2＋濃度と強い正の相関関係があり，Mg^2＋およびCa^2＋のカウンターアニオンとして重要であることを示唆している。また，pHやMg^2＋，Ca^2＋およびHCO₃^－濃度は集水域の標高が高いほど低下する傾向を示し，高標高の集水域では集水域の酸緩衝能が相対的に小さい可能性がある。NO₃^－濃度は平均23.4 μmol L^－1であったが，地点間変動が大きく，およそ1/4の渓流において隠岐諸島における窒素沈着で生じる窒素飽和状態の森林渓流で予測される濃度を超えた。渓流水NO₃^－濃度は集水域最高地点の標高や傾斜角の最大値と最小値の範囲と正の相関を示し，起伏の大きい地形を持つ集水域において窒素流出が生じやすいことが示唆された。

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山陰地方には伝統的な暮らしが現在でも色濃く残り，気候風土に根ざした環境デザインの事例が多く存在する．なかでも風，特に冬季の季節風への対処に様々な工夫が見られる．出雲斐川の築地松（ツイジマツ）は黒松を垂直に刈り揃えた独特の形態の屋敷林として広く知られている．隠岐，久見集落では松のカキヤネ，イタカベ，タケカベ，ササカベといった植物や自然素材を有効に活用した風よけが存在する．中村集落では防風，防砂のための松林が住民の憩いの場，リクリエーションの場として活用されコミュニティの醸成に役立っている．隠岐の他の集落でもイタガコイ，タケガコイと呼ばれる身近な自然素材を使用した風よけが存在する．東出雲町畑集落では，柿の木畑と干柿づくりのための柿小屋（カキゴヤ）が織りなす美しい集落景観のなかで，集落をあげて風土に根ざした特産物である干柿をつくっている．山陰地方では島根半島を中心にして伝統的建築には，棟石（ムネイシあるいはムナイシ）と呼ばれる地産の来待石を加工した棟抑えを屋根に載せるのが特色である．

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A huge volume of lavas and pyroclastic rocks were erupted in Oki-Dogo island in the latest Miocene. They compose the Oki Alkaline Volcanic Group, the Hei Trachyte Group, the Tsuzurao Volcanic Group and the Tokage Trachyte Group. We examine the geology, petrography and geochemistry mainly for the Oki Alkaline Group, and present a magma plumbing story in the latest Miocene age.
The rocks from the Oki Alkaline Volcanic Group are shoshonite, trachyandesite, trachyte and rhyolite, based on their chemical composition and stratigraphy. The trachytes are divided into Trachyte-1 (Nb 35-50 ppm) and -2 (Nb 49-75 ppm), and the rhyolites are divided into Lower Rhyolites (Moderate-SiO₂: 71.4-73.6 wt%), Middle Rhyolites (High-SiO₂: 74.7-75.7 wt%), and Upper Rhyolites (Low-SiO₂: 70.7-71.6 wt%). Lower Rhyolites, Trachyte-1 were formed at the early volcanic stage. Middle Rhyolites, Trachyte-1 were formed at the middle stage, and Upper Rhyolites, Trachytes-1 and -2, trachyandesite and shoshonite were formed at the later stage. Rhyolitic lava domes with different compositions and feeder dikes of trachyte corresponding to individual volcanic vents occur at a number of places. This may indicate that the eruptions took place from several different vents aligned along a circular fracture.
Lower Rhyolites were derived from the lower crust, and Middle Rhyolites were derived from middle crust by partial melting processes. While, Upper Rhyolites, Trachyte-2 and trachyandesite were generated by fractional crystallization from shoshonite magma. The heat source triggered melting of the crusts is inferred to be latent heat of crystallization in the mafic magma. These rhyolite to shoshonite magmas could have ascended through the ring fractures formed by the doming event, and have consolidated as the rocks composing the Oki Alkaline Volcanic Group. After the formation of this group, Cauldron collapse, and it is followed by the eruption of the Hei Trachyte Group and the Tsuzurao Volcanic Group. In the early Pliocene, The tectonic environment of the crust changed from a compressive to an extensional stress field. Then the eruption of the Omine Group and the Tokage Trachyte Group took place.

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A series of medical examinations was performed on school-children of Oki Is., Shimane Pref. in April, 1967.
The investigations consisted of screening tests for acatalasemic gene carriers, ABO blood type tests, and ENT examinations.
Results obtained are as follows:
1. ENT examinations and blood type tests showed average grade and value as those of other places of Japan.
2. Screening tests: Seven hypocatalasemic cases were found out among 4, 831 children examined. Then, emergence of hypocatalasemia on Oki Is. was 0.15%, near to already known Japanese mean value.

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The precise age for the Oki trachyte-rhyolite group was determined by Rb-Sr whole rock isochron method. This trachyte-rhyolite group was formed by a large scale ring fissured eruption on the Oki Dogo Island in the Japan Sea. A regression of the Rb-Sr isotopic data yields an age of 6.8±0.2 Ma with an initial Sr isotopic ratio (Sri) of 0.707176±0.000080 (2a). This age is consistent with the K-Ar age of 6.3 Ma determined by KANEOKA (1970), and is similar to the activity ages of alkali basalts occurring in Oki Dozen Islands near the Oki Dogo Island. The fission track age of 3.6 Ma by SUZUKI (1970) may be caused by some late annealing events. The Sri determined for the Oki trachyte-rhyolite group is very close to that of basic granulite xenoliths included in some alkali basalts. The lower crust beneath the Oki Dogo Island is considered to be composed of these basic granulites which are very poor in alkali metals. It is proposed that the magma of the Oki trachyte-rhyolite group was formed by partial melting of the lower crust with leaving the basic granulite as a residue.

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Orchidaceae, a family of the widespread flowering plants, is reported about 60 species from Shimane prefecture. More than 50% species of Shimane Orchidaceae plants were estimated distributed in Oki islands, an isolated archipelago about 80 km far from Shimane peninsula, and most of them are endangered species. We confirmed the geographical distribution of Orchid Plants in Oki Islands and discuss their conservation status.

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渓流水質の方位分布で気象・水文学的に顕著な特徴の反映が期待でき，円錐形独立峰とみなせる岩木山・鳥海山・大山と屋久島の四山系の放射状流下渓流群の水質調査を秋季・春季・夏季の3回実施した。いずれも日本海・東シナ海に面し，冬季に冠雪する標高1600mを超える高山である。また，最高峰が608mで高山のない円形島の隠岐で春季調査を行った。四山系および隠岐の東西南北の4方位別渓流群の水質平均濃度の比較と，年間降水量・風向，酸性沈着物量や海岸線からの距離との関係を検討した。四山系の方位分布では，全般的に偏西風によって海塩や長距離輸送された大気汚染起因の酸性沈着物で西側の渓流水質濃度が高い傾向が見られた。しかし，岩木山南側ではSO₄^2－濃度が他方位より高く，鳥海山北側ではCl^－やNa^＋濃度が他方位より高くなり，火山・温泉影響と考えられた。3回調査の全渓流水質の平均濃度を四山系で比較すると，屋久島が降水量の多さでH^＋以外の濃度の低さが目立ち，火山・温泉影響の項目を除いた水質濃度では大山が相対的に高い傾向であった。屋久島と大山が海塩や酸性沈着物影響の方位差を反映することがわかった。隠岐では偏西風により西および北側で海塩影響が大きかった。円錐形状，調査地点高度差，渓流数等から酸性沈着物や海塩の渓流水質影響と気象・水文条件との関係を検討するには，四周が海の屋久島が最も適当であることが明らかになった。

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森林渓流の水質調査は全国的に行われているが、離島地域での森林渓流水質は研究事例が非常に限られている。本研究では、島根県隠岐諸島の

における森林渓流水質を調査し、集水域の地勢状況との関係を検討した。の河川分布から、なるべく島全体をカバーするように、上流部に集落等の人為的な排出源がない源流部を採水地に選定して全体で81箇所で採水を行い、pH、電気伝導度、陽イオン類および陰イオン類の分析を行った。隠岐の渓流水は全般的に、NaとClの濃度および電気伝導度が極めて高く、海塩の影響が大きいことが考えられる。また、Ca、MgおよびHCO₃濃度が、低標高で人工林面積割合の大きい集水域において高くなる傾向があった。NO₃濃度は変動が大きく、一部の河川でやや高いNO₃濃度が観測された。この値は、森林の窒素流出が隠岐諸島の窒素沈着量と同等である際に予測される濃度に匹敵していた。NO₃濃度と集水域の標高および集水域内の斜面傾斜角の最大-最小範囲との間に弱い正の相関が認められ、標高が高く起伏に富んだ森林集水域において窒素流出が生じやすい状況にあることが示唆される。

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