One male specimen of the Cancroid Crab was obtained by a smelt-beam trawl from a depth of 15m, off Kushiro, the Pacific coast of Hokkaido, on November 16, 1979. It was identified by Dr. T. SAKAI of the Carcinological Society of Japan as Cancer magister DANA. This crab is one of the important provision resources in U.S.A. (Known as the dungeness crab or common edible crab), ranging along the Pacific coast of North America, from Unalaska, Alaskan Peninsula, south-ward to Montebery Bay, California. It has recently been imported from America to Japan as an edible crab, sold at the markets of Tokyo and Yokohama by the false name of "American swimming crab". Cancer magister is morphologically characterized by having the carapace widest at the last or tenth antero-lateral tooth, and the antero-lateral teeth are low and their tips directed forwards. The postero-lateral borders are unbroken and entire. Fingers of chelipeds are not pigmented with black color. This crab was obtained for the first time in Japan as well as in the north-western Pacific areas. The author is not certain whether this crab was migrated from northwestern coast of America of Alaska, by influence of the cold northern current, or its young or larval crab had been transported by means of the ballast water tunk of a ship. On the other hand, the author's interest has been aroused by the fact that the five American and Alaskan flounder-Embassichthys bathybius had been recorded for the first time in the Pacific coast of Hokkaido by AMAOKA et al. in 1978 (loc. cit.).

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インドのパンジャブ地方から12種の枝角亜目のミジンコが採集され記載した。その内3種は新種である。ここに記録した種は下記の通りである。Alona dhilloni sp. nov., A. pulchella KING, Biapertura sp. indet., Camptocercus kapuri sp. nov., Ledigia ciliata GAUTHIER, Oxyurella singalensis (DADAY), Chidorus sp. cf. ciliatus POGGENPOL, Ch. eurynotus brehmi BISWAS, Ch. parvus parvus DADAY, Dunhevedia crassa KING, Ilyocryptus spinifer HERRICK, I. bhardwaji sp. nov.

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マメヘイケガニ科に属すツノダシマメヘイケガニ属はいずれも小形種で,多くは深海産であって個体数も少ない。眼柄が固定されているのが特徴的で,眼そのものも機能を果たしていない。眼柄と額角の相対的な長さから2つのグループ,すなわち,眼柄の方が長いquadratus群と額角の方が長いgranulatus群に分けられる。これが自然分類にかなっているかどうかは別として,何よりも便利である。ほとんどは各群の中の亜種として扱われてきたが,それは単に古い命名法を継承しているにすぎない。いずれも独立種と考えることが可能で,そうすると既知種はインド西太平洋海域から8種,西大西洋から4種,東大西洋から2種ということになる。日本からはツノダシマメヘイケガニC.japonicus BLASS, 1922,イソドツノダシマメヘイケガニC.andamanicus ALCOCK,1905,ツノナシマメヘイケガニC.curvirostris SAKAI,1965が知られている。ここに記載した新種は房総半島野島崎沖から得られた雌1個体にもとづいている。すべての歩脚が失なわれているが,額角と眼柄の形態によって他種から容易に区別される。眼柄がほとんどまっすぐに固定され,また額角が細くて眼柄の半分ほどに達することが著しい特徴である。和名はウミタカツノダシマメヘイケガニを提唱する。

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Favicola(キクメイシヤドリガニ属,新称)はFIZE and SERENE(1957)によりTroglo-carcinus属の亜属として設けられ,5種が知られている。形態,生態ともCryptochirus(ケブカサンゴヤドリガニ属)に酷似し,外形だけでは区別することができない。ほとんど唯一ともいえる区別点は,Fovicolaの雌では3対の腹肢のうち第1腹肢に外枝があるのに対し,Cryptochirusでは3対の腹肢すべてに外枝を欠いていることである。McCAIN and COLES(1979)が,ハワイ産のHapalocarcinus marsupialis STIMPSON(サンゴヤドリガニ)とPseudoha-Palocarcinus ransoni FIZE et SERENE(ヒメサンゴヤドリガニ)において二叉型腹肢の数が必ずしも一定していたいことを報告しており,FavicolaとCryptochirusを雌の腹肢の状態によってのみ区別することは問題があるかもしれないが,本報告で扱った標本では雌の腹肢は安定しており,属名はFavicolaを生かした。問題となった種はいずれも瘤を作る種であり,穿孔性の種よりも形態の上でも特殊化が進んでいることが推察される。本報告ではF.rugosa(EDMONDSON)(キクメイシヤドリガニ,新称),F.helleri(FIZE et SERENE)(ヤエヤマキクメイシヤドリガニ,新称)の2既知種とF.japonica sp. nov.(ヤマトキクメイシヤドリガニ,新種新称)を記録し,新種を含めた全6種に対する検索表を作成した。

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三浦半島,江奈湾の林床に生息するアカテガニを1978年から1980年に採集しその生長,脱皮,抱卵等を観察した。この調査地点では雌が雄よりも多数捕獲されるが生息数は同数と推定される。活動期は5月から10月である。活動と同時に交尾が観察されるが抱卵時期は6月から9月までで,最盛期は7月である。産卵回数は,1年間に少ない個体でも1回,平均2回,多い場合には3回である。脱皮時期は5月から9月で初夏と初秋に脱皮が多い。脱皮回数は生長と共に減少する傾向があるが平均2回である。産卵された卵は雌の腹肢に約27日間抱卵され,海にゾエアとして放卵される。1ヶ月後に江奈湾の干潟でもメガローパが脱皮してカニとなる。1,2年目は近くのアシ原で脱皮を繰り返して生長し,生後,3,4年目に今回の調査地点とたった林床に生息場所を移動して交尾,産卵活動に加わる。甲殻の幅が25mmのアカテガニは生後8,9年と推定されるが,平均寿命は5,6年と考えられる。

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Zoeae of the five varunid crabs, Eriocheir japonicus DE HAAN, Hemigrapsus sanguieneus (DE HAAN) , H. Penicillatus (DE HAAN) , H. longitarsis (MIERS) and Gaetice depressus (DE HAAN) , of the family Grapsidae were successfully reared in the laboratory from hatching to the megalopa stage. Artemia nauplii were given as food. In this paper, the zoeal stages of all the species are described in detail and those of H. longitarsis are figured. The zoeae of these species are compared with those of the other members of the Subfamily Varuninae so far studied by previous writers. As in H. nudus, H. oregoniensis and Acmaeopleura parvula, the five species herein dealt with have five zoeal stages before transforming into the megalopa. The zoeae of the varunid crabs are very similar in structure one another, although minor differences are found among different genera. As to the five species, zoeae of genus Hemigrapsus are different from those of the other two genera (Eriocheir and Gaetice) by the occurrence of one small seta on the anterior lateral surface of scaphognathite in the last stage and also in setation of basal endite of maxilla I in stage IV. Furthermore, zoeae of the two species of genus Eriocheir and the five species of Hemigrapsus can be distinguished from those of the genera, Acmaeopleura and Caetice, by having lateral carapace spines. Among the nine known species differences are found in the presence or absence of chromatophores on protopod of maxilliped II, mid-lateral spines on abdominal segments II and III, setation on endopod of maxilliped II, and the type of antenna II.

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Larvae of six species of the subfamily Acanthonychinae (family Majidae) : Pugettia quadridens quadridens (DE HAAN), P. q. intermedis SAKAI, P. incisa DE HAAN), P. similis Rathbun, Menaethius monoceros (LATREILLE) and Huenia proteus DE HAAN, were successfully reared in the laboratory from hatching to the megalopa stage by feeding on Artemia nauplii. The numbers of zoeal stages are only two in the six species. These zoeae may be classified into two groups. In the first group. to which the genus Pugettia, chromatophores are present at the bases of rostral and dorsal carapace spines and on protopod of maxilliped I, setation of endopod of maxilla I is 4・0-1, that of inner lobe of coxal endite of maxilla II is 1:3, caudal furca of telson is twice as long as width of telson, and the articulation of telson occurred in stage II. In the other group including genera Menaethius and Huenia, no chromatophores are present at the three parts, setations of endopod of maxilla I and inner lobe of coxal endite of maxilla II are 4・1-0 and 1:4, caudal furca and width of telson are about equal in length, and the articulation disappears in stage II. Specific differences in the characters of zoeae are as follows. In genus Pugettia (the first group), P. incisa has setation of 3 on endopod of maxilla II, but the other three species have 4. Furthermore, P. q. intermedis has nine setae on basal endite of maxilla I in stage II, in contrast, P. q. quadridens and P. similis possessing ten in the same stage. In the two species of the second group, M. monoceros has rostral spine, but neither dorsal nor lateral ones on carapace and setation of 5 on endopod of maxilla II, whereas H. proteus having rostral and dorsal spines, and setation of 4.

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フィリピンではウシエビポストラーバは養殖用種苗に利用されているが,時折査定ミスがみられる。そこでクルマエビ属ポストラーバの査定を試み,2種,2グループに分類した。1) P.monodon:大型で色素胞がよく発達,第1触角内鞭は外鞭の2倍以上, 2) P.semisulcatus:小型で尾扇中央部で色素胞を欠き,内鞭は外鞭の1.6-2倍, 3) P.merguiensis group:小型で色素胞の発達が極めて貧弱で,内鞭は外鞭の1.6倍以下, 4) P.japonicus group:中間型で,色素胞はよく発達するが,第6腹節背面に小棘が列生し,額角は眼の先端を越えない。

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The present paper deals with allomatric growth between carapace length and carapace width of tadpole shrimp, Triops granarius (LUCAS) living in the paddy field, Takatsuki, Osaka Pref., with special reference to its population.

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岡山県の児島湖に生息するテナガエビの漁業生物学的研究のため,1979年4月から1980年3月までの1ケ年間,毎月地獄網と呼ばれる小型定置網による採集を行なった。調査総数は19,828個体で,それらの体長は12〜89mmであったが,この中に2個体の奇形を発見した。この種はもちろん,テナガエビ属の自然環境下における奇形については,これまでほとんど報告されていないので,ここに紹介する。これら2個体はいずれも雄で,一方の個体は第2歩脚のはさみが強く下方に曲っており,その他の節の長さや大きさに異常は認められないが,はさみ脚としての機能を正常に果しているとは思われたい。他の個体は2つに分かれている尾節の先端部を持ち,右側は棘と剛毛の数や長さが正常であるが,左側では棘だけが縦に列んでいるのみで,末端の剛毛も少ない。これら奇形の原因としては,従来から言われているように脱皮時や再生時に何らかの外圧を受けた結果であると思われる。

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A simple technique is described for obtaining well-spread metaphases from solid tissues of Crustacer. The procedure of chromosome preparation was as follows : 1) Specimens were injected intraperitoneally with colchicine solution at the dosage of I pg per 1μg body weight five hours before being dissected. 2) Remove antennal gland and testis, and cut them into 3mm pieces where necessary. 3) Place tissue pieces in the hypotonic solution (distilled water or 0.01M KCl) for 10 minutes. 4) Add small quantity of Carnoy's fluid (3:1 ethanol acetic acid). 5) Fix in at least two changes of Carnoy's fluid for at least 15 minutes each. 6) Pick tissue pieces up from Carnoy's fluid by a forceps, and tap to spread them on a slide glass for a proper density of cells. 7) Drop Carnoy's fluid on the slide from a fine pipet. 8) Dry quickly by flaming. 9) Stain with 2% Giemsa for 15 minutes. Large numbers of slides of chromosome can be made easily and rapidly using this procedure.

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The habitats, nest burrows, hibernation, awaking, molting, copulation. oviposition, egg-bearing, zoea-liberation (spawning) , beach landing of the tiny young, and so on of the land-crab, Sesarma (Holometopus) haematocheir (DE HAAN), were studied from April, 1979 to November, 1980. Field observation was made in the rocky shore near the Sado Marine Biological Station of Niigata University located on the west coast of Sado Island in the Japan Sea. When the ground temperature (GT) fell gradually 16℃, the crabs emerged from the nest and went to the beach for feeding. Molting occurred from late June to middle September, although in mother crab it took place since August after the release of zoeal larvae. Copulation was found from late June to early August, and the frequency of copulation and next oviposition in one spawning season were two to three times per crab. Zoea release took place almost every night about one or two hours after sunset (ca. 19:00) during the period from late July to early September, although no spawning was encountered in stormy weather. Beach landing of an infant crab just metamorphosed from megalopa was seen in late September, and the first molting occurred in a pool two or three days after landing. Difference between the spawning behavior of this land-crab occurring in the Japan Sea coast and in the Pacific coast was discussed in relation to the difference of the tidal changes in the both coasts.

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The ecological distribution of phytal amphipods on seaweeds were investigated in a Sargassum bed at the coast of Tomioka Peninsula, Amakusa, Kyushu. Eight plants of 4 Sargassum species were collected underwater by the vertically stratified sampling method in May when these seaweeds fuliy grown up. By this sampling, 10 species of caprellids and 21 species of gammarids were obtained. The similarities among epiphytic amphipod assemblages of each host plant were analyzed for Caprellidae and Gammaridea respectively. These assemblages resembled each other, consequently it was speculated that these epiphytic amphipods generally have no specific preference to the host plants. Simultaneously, two groups were recognized in both taxa, namely, one group consists of S, patens and S. horneri which were collected in the outer part of the Sargassum bed, another is S. thunbergii and S. hemiphyllum which mainly flourish inside. The difference seemed to be caused by the factors which related with wave action or other hydrodynamic conditions. In the vertical distribution of the biomass of each alga, the weight of higher part was normally heavier than that of lower part, and this tendency was also observed in the individual number of amphipods on each part. Vertical distribution of 6 species of amphipods (Caprella decipiens, C. danilevskii, C. tsugarensis, Ampithoe orientalis, Aoroides columbiae, Pontogeneia rostrata) showed high positive correlations with those of seaweeds biomass. Exclusive of S. horneri, C. monoceros and Phliantidae sp. 1 also showed positive correlations with the vertical distribution of seaweed biomass like other species. On S. horneri, however, they mainly occurred on the lower part of seaweed and showed negative correlation.

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1976-1977年にかけて南西海区水産研究所及び大分県水産試験場が協同してSmith-Mclentye type bottom samplerを用いて別府湾全域の海底の砂を採集し,生物相を調査した。ワレカラ類はPseudoproto fallax MAYER・Protogeton inflatus MAYER・Caprella(S.) gigantochir MAYERの3種だけであった。これらの種は総べて湾口に近い砂地の海底から採集された。ワレカラ類が少ないのは,別府湾が八阪川・大分川・音津川及び大野川などの河川によって海水が汚濁されているためと思われる。

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