The genus Enoplometopus was placed in the Nephropidae of Infraorder Astacidea. Based on the morphological characters, it is classified in the Axiidae of Infraorder Anomura (HOLTHUIS 1946, 74, 83). Little have been known about the larvae of this genus. Obserations on the larvae of E. occidentalis are reported here. Larvae were cultured for 55 days until 8th zoeal stage. The larvae bear large 1st pereiopod from 1st zoea, and they use the chelae for feeding. Other larval characters were similar to those of the Axiidae: long rostrum,shape of endopod of 1st maxilipeds, pereiopods 4th and 5th have delayed development, and post marginal setae on the tail. These characters indicate that E. occidentalis may belonging to the Axiidae. The 8th zoeal stage closely resembles the larva described for Enoplometopus sp. by GURNEY(1938). The larva of Nephrops sp. described in that report is also similar to the 2nd zoeal stage of E. occidentalis. It is proposed that these two larvae described by Gurney belong to Enoplometopus.

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The First zoeas obtained from egg beared female of Cyrtomaia owstoni were reared in the laboratory. Three parent crabs trowled from Suruga-Bay,300m depth, off Heda, Shizuoka prefecture on Dec.26, 1983. Among them, one egg beared crab was found 45 days after, and hatching occured 100 days after catching. The first zoea was 2.8mm in length rostrum to dosal spine. Zoeal featurs as follows ; dosal spine comparetively long; antennal exopod ends three forked; endopod of maxillule 2 segmented with bearing 4 teminal plus 2 setae and I setae each: endopod of maxilla beared 4 terminal setae, basal and coxal endite bilobed; endopod of 1st, maxilliped 5 segmented with setation 3-2-1-2-5 and endopod of 2nd. maxilliped 3 segmented with setation 0-1-4. Those features were very similar to C.hispida first zoea reported by WEAR and FIELDER (1985).

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Distribution pattern of the porcelain crab, Petrolisthes japonicus found in the intertidal boulder beaches of an oceanic island, Chichijima, Ogasawara (Bonin) was compared with that in a continental island, Zamami, Okinawa (Ryukyu). P. japonicus occupied widely over the entire intertidal boulder beaches in Ogasawara, where only one species of the porcelain crab inhabits. In Okinawa, however, P. japonicus was restricted in the middle intertidal zone and its habitat was significantly narrower and higher than those on Chichijima. In Okinawa, six other species of porcelain crabs, P. hastatus. P. lamarckii, P. fimbriatus, P. tomentosus, P. carinipes and P, asiaticus coexisted there, and the distribution patterns of them can be clearly divided into two types: the middle intertidal type, (P. japonicus and P. hastatus) and the lower intertidal type (P. asiaticus, P. tomentosus, P. lamarckii. P, fimbriatus and P. carinipes.

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The distribution of two species of fan lobster, Ibacus ciliatus ciliatus and I. novemdentatus, was examined, based on trawl surveys in the East China Sea. The both species occured zonally in the shelf of 33° N to 26° N along the shelf edge. Area of high abundance was in the waters north of 31° N for I. c. ciliatus and south of 29°30′ N for I. novemdentatus. I. c. ciliatus inhabited mostly in the areas of 120m and deeper, compared with I. novemdentatus in the areas of 100-120m depth.

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Fighting for a shelter between Palaemon pacificus and P.serrifer were investigated in aquaria. In both interspecific and intraspecific fighting,the smaller individuals were usually eliminated by the larger ones from the shelter. In the case that smaller individual was a winner, P. serrifer won more often than P. pacificus although P. serrifer was smaller. The second pereiopod was longer in P. serrifer than in P. pacificus. P. serrifer made up for smaller body size by larger second pereiopod length than P. pacificus relatively.

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The growth and the reproduction of the spider crab, Tiarinia cornigera was investigated at the Banda Marine Laboratory of Tokyo University of Fisheries. Chiba prefecture, and the outline of the life history was determined. The larvae of T. cornigera hatch in June to September, and metamorphose to juveniles crabs in 7 to 10 days. The juveniles grow rapidly in autumn. In winter the growth stagnates, but in spring again they grow rapidly. In June to July the puberty molt which is also the terminal molt occurs, with the development of the second sexual characteristics. Soon they mate and spawn. In a reproductive season a female spawns 4 to 6 times. At about 20 days after spawning the larvae hatch and a further brood deposited. In autumn the most of adults finished breeding are die out. It is suggested that the life span of T. cornigera is about one year in this study area.

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Giant spider crab, Macrocheira haempferi (TEMMINCK), with a median rostral tooth instead of a pair of rostral spines, and Japanese spiny lobster, Panulirus japonicus (VON SIEBOLD), with the heteromorphic antennule in place of right eyestalk, are recorded respectively from Suruga Bay and the coast of the Boso Peninsula, central Japan. It is definitely said that the malformation of the rostrum is caused by the extended true rostrum being not descended during its development as a septum of the antennular fossae of both sides. On the other hand, the heteromorphic antennule is rather rare in the field, only with some records in spiny lobsters and crawfishes, and also in a freshwater atyd shrimp, but HERBST (1895-1916) and some recent authors experimentally caused the heteromorphic antennules not only in the shrimps and lobsters, but also in the hermit crabs and porcelain crab. According to them, the heteromorphic antennules are functional in response to mechanical and olfactory stimulation, and such heteromorphosis is produced only when the optic ganglion is severed along with eyestalk.

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[in Japanese]

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