A pyramidellid species which is ectoparasitic on a trochid snail Umbonium (Suchium) moniliferum (Lamarck, 1822) in Tomioka Bay, Western Kyushu, has been reported by several authors as "Odostomia desimana" or "Odostomia sp.". Since detailed morphological investigation on this species revealed that it is neither Odostomia desimana Dall & Bartsch, 1906 nor any of hitherto known species, this is described as a new species Boonea umboniocola. Main conchological differences of this new species from many of the other similar species in the Indo-West Pacific area are, tall and long ovate shell, multiple numbers of whorls, and less constricted sutures.

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Claviscala turrita n. sp., Claviscala solar n. sp., Mazescala koyamai n. sp., Lampropalia enamelis (Kuroda, MS) n. sp. and Epitonium (Kiiscala) laxatoides (Kuroda, MS) n. sp. are described. These new species were all collected from deep waters off Kii Peninsula, Japan. Claviscala turrita resembles Claviscala terebralioides Kilburn, 1975, morphologically, but differs in having more axial ribs and deeper suture. Claviscala solar also resembles C. terebralioides, but it is distinguishable by weak axial ribs and black spotted shell. Mazescala koyamai has similarity with M. thrasys Iredale, 1936, morphologically, but differs in having more axial costae and slender shape. Lampropalia enamelis is very close to Lampropalia nitida Kuroda and Ito, 1961, but is is distinguishable by the protoconch and the surface. Epitonium (Kiiscala) laxatoides resembles Epitonium (Nitidiscala) hancocki Dushane, 1970, but differs in having detached teleoconch.

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サザエTurbo(Batillus)cornutus Lightfoot, 1786は古来から食用に供され, 日本人にとって最も馴染みのある巻貝の一種である。波部・小菅(1967)やAbbott and Dance (1982)などによれば, 本種は北海道南部以南から九州にいたる日本列島の沿岸, 中国大陸, 朝鮮半島の潮間帯下の岩礁に生息するとされている。筆者らは本種の分布域の標本群を検討した結果, これまでサザエとして扱われてきた中国大陸沿岸産の個体群は, 日本や韓国産のサザエと明瞭に区別され別新種と認められたのでここに記載報告する。新種ナンカイサザエTurbo (Batillus) chinensisの多くの形態的特徴はサザエと類似しているが次の点から明瞭に区別される。(1) 石灰質の蓋外面はより膨らみ, 螺肋が不明瞭でかつより微細な顆粒で被われる。(2) 棘状突起がより小さく管状にならず, その数が多い。また, 体層の肩に生じる棘状突起列の位置がやや高い。(3) 体層の螺肋に二次肋および三次肋が発達する。(4) 螺塔がより低く, 殻高は大きな個体でも7cm程度にとどまる。本新種は中国逝江省舟山群島から南は広東省香港付近までの岩礁海岸に分布し, 水深0∿3mに多い。なお本種の模式産地は広東省汕尾(Shanwei)である。

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Leucotina was established at first as a genus of the family Acteonidae, but later it had been allocated in the family Pyramidellidae. But, Ponder (1987) speculated that this genus may belong to the family Amathinidae based on shell, though soft part characters were not comfirmed. The present investigation on not only shell but also soft part characters of two Leucotina species including the type species of this genus concluded that this genus is decidedly a member of the Amathinidae.

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蒼鷹丸によって採集されたヒザラガイ類の第3報であるが, これまでの報告(Wu & Okutani, 1984, 1985, 1986)の種よりも浅い所から採集されたケハダヒザラガイ科の3種につき記載した。ミツカドヒザラガイCraspedochiton pyramidalis (Taki, 1938)伊豆七島沖, 水深70-115m。タテヤマベニヒザラガイNotoplax "tateyamaensis Taki, 1962"本種はIs. TakiのMS名であるが, Bergenhayn (1933)がN. stewartiana Thiele, 1929(ニュージーランド産)と同定したものかもしれない。伊豆七島135m。ウスコケヒザラガイN. hilgendorfi Thiele, 1909。伊豆七島沖110-160m。

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日本の中新統稀産種のツルナガウミタケガイモドキ(Pholadomya turunagai Tan)を鳥取県南西部の多里累層から記載した。本種はかってPholadomya cf. puschi Goldfussとして報告されたが(Yokoyama, 1927), 殻頂角の大きいこと, 放射肋の数が多いことからTan(1940)が台湾の海山層から報告したPholadomya turunagai Tanに同定される。本種は共産する他の二枚貝化石が離弁でラミナに沿って産出するのに対して, 合弁で殻の長軸が傾き, 現生種のミルクイガイTresus keenae (Kuroda and Habe)の姿勢に近い状況で産出することから, 深潜没者で, 生息時の姿勢を保持しているものと考えられる。現生種のウミタケガイモドキは50∿200mの海域に生息するが, 本種は共産する軟体動物化石, 有孔虫化石の群集構成および岩相から判断すると, 熱帯から亜熱帯の上部浅海帯の砂底に生息したものと考えられる。

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In order to analyze the factors determining the intra-individual distance among the freshwater mussel, Anodonta woodiana, the survey was carried out at a small pond (200 m^2) in Toyonaka City, Osaka Prefecture in March 1985. After draining the small pond, 32 quadrates (32 m^2) were set up on the bottom of the pond. And then, positions of the total 492 mussels were recorded. The sex ratio (♀/♂) was 1.33 and the incubatioin ratio in females was 61.3%. The short distance between two individuals were from 0 to 10 cm in many cases (75.4%, n=312). This fact shows that the mussels have the concentrated patchy distribution in the pond. Based on the distance among individuals, the mussels were divided into three groups, which were compared in terms of the sex ratio and the incubation ratio. Most of the males live in relatively short distance (less than 10 cm) between them, many females keep larger intervals in between (more than 10 cm), and their incubation ratio was high. Some females with eggs and larvae stay on in their groups, and others do not. In short, intra-interval distance among the mussels may depend on their breeding conditions.

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