寄生性原生動物については今迄にも色々報告されているが,甲殻類に寄生するものについては極めて少ない。甲殻類は一般に,脱皮を行なうので鰓や体表面に寄生した原生動物等はその都度脱落してしまうが,次の脱皮までの間に,有機物や下等藻類等が鰓に附着すると共に非常に多数の原生動物が再度寄生する。そのため養殖エビ等は大量斃死を起こすと云われている。著者は,近年,数種の甲殻類の鯛に寄生する原生動物について若干の知見を得たので今回はについて報告する。尚,この調査研究にあたり生前懇切な御指導を賜わりました恩師の故福井玉夫博士の霊前にこの報告論文を捧げます。本研究は1954年〜1956年,1961年〜1967年の2期について行なった。材料は,内湾に面した汚れた海岸(横浜市)と,外海に面した清澄な海岸(油壷等)とで比較するため採集した。調査研究の方法は,はじめ生鮮個体について,ついで核染色をしたのち同定を行なった。そのあと次の諸点につき検討した。1)個々のの鰓における原に動物の寄生位置及び数。2)鰓の外鰓葉及び内鰓葉の別動寄生状況3)各鰓葉節と寄生との関係4)の雌雄差による寄生状態5)季節別の寄生状態6)採集場所と原生動物の相関性等について行なった。の鰓は図1の示したように内,外鰓葉共左右各5葉ずつ合計20葉あり,このうち雌雄共に第1鰓葉は,内外共に著しく小型化しており,雄の第2内鰓葉は雄性突起として変形している。今回供試したの数は合計1506個体で,内湾に棲息のもの876個体,外洋に面した所に棲息のもの630個体て,雌雄比はほぼ1:1こであった。今回の調査研究で見出された原生動物は,Ciliata(繊毛虫類)が3科9属25種,Suctoria(吸管虫類)が3科5属9種であり,内湾棲息のには内湾性(brackishwater)の原生動物が殆どであり,外洋に面した所のものでは外洋性の種が主で,ごく数種が両水域から見出された。いずれの場合もEpistylidaeとVaginicolidaeが優占種であった。又,寄生部位も,内鰐葉,外鰐葉の別,及び,各第1〜第5鰓葉の別,そして各鰓葉の寄生部位に著しい差が認められた。しかし,これらと原生動物の種類との間には差は認められなかった。季節と寄生原生動物の問には明らかに関連がある。これは,主に水温の季節的差による消長と思われる。の採集地別による寄生種の差も認められた。

抄録全体を表示

Legged animals exhibit adaptive and resilient locomotion through their inter-limb coordination. Our motivation is to elucidate the inter-limb coordination mechanism underlying various legged animals from a unified viewpoint. Thus far, many studies have focused on animals with a few legs, e.g., bipeds and quadrupeds, and those with many legs, e.g., myriapods. However, the two extremes were not connected because those with intermediate number of legs, e.g., isopods, have been less studied. Accordingly, in this study, we focus on the locomotion of sea roaches which have 14 legs. As a first step, we observed the locomotion of sea roaches and found that they change their gait pattern depending on their walking speed and morphology.

抄録全体を表示

The semi-terrestrial isopod, Ligia exotica, lives on the seashore among jetties and rocks. It shows poor resistance to desiccation and cannot live without seawater. When it is exposed to dry conditions, its body weight decreases to 90% of the initial weight within three hours. When subsequently presented with wet paper, legs VI- and VII-th of the animal are firmly apposed and stationed for a while. Since the body weight had increased after this behaviour, a pair of caudal legs seemed to play an important role to absorb water. Morphological observations of those caudal legs revealed that there is a series of thin cuticler protrusions, oriented in several parallel lines, which is developed on from 2nd to 5th podite of the VI-th preiopod and 6th podite of the VII-th pereiopod. When we immersed each leg from the tip, the water flows along those series of thin cuticler protrusions. The animal absorbs water along those surface structures of the caudal legs.

抄録全体を表示

タイプ標本に基づいてLigidium japonicum を再記載した．ニホンヒメは以下の点で再 定義される：尾肢内肢が尾肢外肢の 1.1–1.3 倍である，第 1 腹肢外肢に長い刺毛がある，第 2 腹肢内肢の先端はU 字である，内側に複数の棘がある，内側の切り欠きの前方の外側には棘が一つある．第 2 腹肢内肢の先端の内側の棘の数の変異がタイプ標本と千葉県の標本の間で見られた．

抄録全体を表示

We have aimed to alleviate pain in diabetic patients by developing minimally invasive microneedles. In this study, a microneedle with a liquid suction mechanism was developed to extract a target volume of 0.3 μl of blood. Our approach mimics the capillary force and water-absorbing behavior of water strider legs, and we fabricated a plate to imitate their microstructure. The flow rate of water and blood was measured to evaluate the performance of the microneedles. The desired blood absorption volume was achieved by applying hydrophilic treatment to the microstructure. Microneedle with a liquid suction mechanism was developed based on the principle of improving capillary force by adding microstructures that mimic the legs of a crucial carp. The effects of microstructure shape and density on suction speed were evaluated using water and blood as suction targets.

抄録全体を表示

1) には顕著な交替性転向反応がみられ, 強制転向角が大きいほど交替率も大である。
2) 交替率は転向後撰択点に達するまでの時間の増大, または作業量の増大によつて減少する。つまり, 時間と作業量は共に先行転向の効果を'忘却'させる要因として作用していると思われる。
3) 交替性転向反応は, 左右の足の作業量の違いからおこる現象として説明できる。

抄録全体を表示

1. Only a few data have been reported on the periodit behavior of animal populations. The present paper records the daily periodic journey of the shore isopod populations observed under natural conditions. Observations were performed in 1954,on the intertidal rocky shore near the Seto Marine Biological Laboratory and at Fuji-Shima in Tanabe Bay, from late July to early August, and on the rocky shore at Karo, Tottori City, in August. 2. The shore isopods, that passed night among crevices of rocks above the tidal mark, commence the morning journey just before sunrise. They creep out from the resting places and march down towards the beach making several lines, getting over many stones, rocks or other obstacles, and at last reach their feeding places on the intertidal rock surfaces. They stay there in the daytime. In the late afternoon they begin to retire to their resting places, and the evening journey ends just before sunset. 3. Thus, they travel twice in a day, in the early morning and in the late afternoon. These periodic movements seem to be maintained by the combined action of daily changes of solar illumination and changes in the internal physiological conditions of animals (chiefly of conditions of alternative hunger and satiety). Such elements as air temperature, relative humidity or changes of tidal level may have not affected soundly these periodic movements. 4. It was observed that most individuals behave in aggregation throughout a day, whenever they are resting, migrating or eating. These aggregations are usually composed of several sub-groups, and the age of the members of each sub-group is nearly similar, i.e., animals have a tendency to make agers-assenblages. No sexual groups are recognizable. It is noticeable that the groups composed of younger individuals commence the journey always earlier than those composed of older individuals, regardless of morning or evening. 5. When migrating, the animals move from rock to rock, as it seeking an adequate pathway to the shore or to the resting place. It is thought that such pathways are characteristic to each populations of different habitats, so all members of the same population seem to march on the same way at the journey. 6. It is found that the aggregation has a sort of social organizations, namely, dominance order is recognizable ; the larger the individuals, the more they are dominant.

抄録全体を表示

長い年月をかけて進化した生物の体には、生息環境に適応した優れた機能が備わっている。その優れた機能を活用することで、さまざまな工業製品が開発されるようになった。こうした手法は、バイオミメティクス（生物模倣技術）と呼ばれ、近年、スポーツ用品や建材、医療などの幅広い産業に利用され始めている。バイオミメティクス研究は、電子顕微鏡技術とともに幕を開けた。その電子顕微鏡の限界を乗り越える技術「ナノスーツ」の登場によって、「生きたままの観察」が可能になり、第2の幕が上がろうとしている。さらに生物の画像とその生態や機能を集積・共有し、研究を促進する動きもある。生物が何億年の歴史の中で獲得してきた独特の機能を学び、応用することで、省エネや安全、環境適合の持続可能な人類文明の創造に、弾みをつけようとしている。

抄録全体を表示

Some taxonomical revisions on Japanese terrestrial isopods were proposed, a brief history of isopod taxonomy in Japan was described, and the species ascertained by myself were listed.

抄録全体を表示

1) ONDO and MORI reporded the outline of the periodic journey of the shore isopod population in 1956. The present paper deals with some results of my further investigations executed at the natural habitat. 2) The isopod population migrates periodically twice a day as mentioned previously. From investigations executed at the natural habitat, it was concluded that there was no direct interrelations between the periodic journeys and changes of tidal level. They always go towards the beach early in the morning and reach the feeding places on the intertidal rock surfaces. They repeat the following characteristic behavior, i.e. when the tide rises, they retire to the high part of drift line but do not return to the resting places, on the contrary, when the tide lowers, they again return towards the drift line. Thus, the range of feeding and migration was limited by the changes of drift line in the daytime, as shown in Fig. 1. In the late afternoon, they commense their evening journey to return to their resting places just before sunset. Thus, it was ascertained that the periodic journey of the isopod population is influenced by periodicity of environmental factors as daily changes of solar illumination, but on the other hand, it was also true that the internal physiological conditions (chiefly diurnal changes in conditions of alternative hunger and satiety)and interspecific relationships are also important. From the ecological point of view, the periodic journey of the isopod population belongs to the recurrent movement. 3) An attempt was made to learn something of the nature of the physiological conditions in the detailed forms of the daily cycles of the melanophores and of the daily changes in conditions of alternative hunger and satiety. The melanophores were staged at hour intervals through 24 hours. The average stage of melanophore was determined by estimating the average melanophore state on the dorsal surface of the walking leg, antennae and dorsal surface of the body. The classification based upon HEWER's study was used, with 1…contracted, 2…slightly stellate, 3…stellate, 4…slightly expanded, 5…expanded, 6…fully expanded. A detailed analysis of the character of the diurnal changes in the melanophores of M. exotia confirmed the precision of the 24 hour endogenous rhythm as indicated in Fig. 2. On the other hand, to see clearly the changes in conditions of alternative hunger and satiety, 20-30 individuals of the same agers-as-semblage(individuals of 20-30mm body length)were collected at hour intervals through 24 hours at the natural habitat and afterwards, dissected to confirm whether their conditions of alternative hunger and satiety. Generally, all members of the agers-assemblage just mentioned taking morning journey were in conditions of hunger and those of evening journey were sufficiently fed. Therefore, the state of such internal physiological conditions affect the time when the isopod population begins to take morning and evening journeys. From these experiments, it is pointed out that the time when all members of the isopod population begin to take morning and evening journeys was synchronized with the changes in conditions of alternative hunger and satiety. These facts are indicated in Fig. 2. 4) When migrating, all members of the same population run from rock to rock. To investigate the behavior patterns, some experimental analyses were carried out under natural conditions. As a result, it may be concluded that the isopods seek an adequate pathway to the feeding or resting places with their thigmotactic sense. These results are shown in Table 1.

抄録全体を表示