Marine Biological Studies on Bivalve-Inhabiting Hydrozoans in Southern Japan, especially in Islands washed by Kuroshio

1.取自对马群岛的日本真首乌贼中间形态的水母从寄主双壳类中释放的时间在夏季和冬季不同。2.取自广岛竹原的日本真对虾南型，全年与高山真对虾共生，除冬季外，繁殖周期较长。3.取自广岛竹原的日本真对虾，除越冬外，其繁殖周期较长。3.取自广岛竹原的南型真对虾，在傍晚几小时左右释放水母。在75%和50%的水温条件下，未发育出水母芽，水母不能取食。5.在不同水温条件下与寄主甜菜夜蛾一起饲养水母。在较低的温度下，一周后停止释放水母，并减少了息肉的附殖体。6.翡翠贻贝是日本贻贝的新寄主双壳。这种共生关系从未在较大的双壳类个体中发现，而是仅在较小的双壳类个体中发现。7.第二个记录的双壳类真甲藻的息肉共生现象是从对马群岛采集的。然而，对这些息肉的鉴定是失败的，因为没有通过饲养它们获得水母。

1.Release time of medusae of the intermedia form of Eutima japonica taken from the Tsushima Islands from the host bivalve, differed between summer and winter seasons. In winter, Eugymnanthea japonica ceased to release its medusae earlier than Eut.japonica.2.The southern form of Eut.japonica taken from Takehara, Hiroshima was commensal with M.edulis galloprovincialis throughout the year, and its breeding occurred for a long period except for winter.3.The southern form of Eut.japonica taken from Takehara, Hiroshima showed a daily periodicity that the medusae were released in a few hours around evening.4.The polyps of Eug.japonica taken from Shirahama were reared under the different conditions of salinity. Under the 75% and 50% conditions, no medusa buds were developed and the polyps became to be impossible to feed.5.The polyps of Eug.japonica were reared under the different conditions of water temperature together with their host, M.edulis galloprovincialis. Under the lower temperature, they ceased to release the medusae after one week, and the hypostome of polyp was reduced.6.Perna viridis was found to be the new host bivalve of Eug.japonica. The commensalism was found never in larger individuals of the bivalve but only in the smaller ones.7.The second record of the commensalism of polyps of Eugymnanthea sp.with a bivalve, Ruditapes philippinarum was taken from the Tsushima Islands. The identification of the polyps, however, was failed, because no medusae were obtained by rearing of them.