A small colony of Periophthalmus modestus was found during our survey of fauna at the mud flat of estuary of the Tama River on 26th of July, 1998. The species is ranked as the "extinct B" according to the Red Data Book of the Kanagawa Prefecture. Judging from the previous reports on fish fauna in this area, the colony is the first record of the resident population in the Kanagawa. A recruitment of juveniles was found in the colony after the rainy season of September. From this evidence, the colony seems to be sustainable throughout a year. We collected one specimen from the colony, then preserved and registered it at the Kanagawa Prefectural Museum of Natural History (KPM-NI). Descriptions are made for the morphology of the registered specimen, the behavior of population members at the collecting site and that of one individual in captivity. Periophthalmus modestus was widely distributed in the Bay of Tokyo in former years. However, the present habitat of the species is restricted to some small areas, because natural mud flat with some extent is indispensable to maintain the population. It should be necessary to monitor the environmental condition in there for the protection of the colony.

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A research on the seasonal activities of medusas was conducted from January 1997 to August 1998 in and around Enoshima-Shonan Port located at the innermost corner of the Sagami Gulf. The research confirmed sixteen species of hydroid (Hydrozoa), one species of box jellyfish (Cubozoa), and six species of scyphomedusa (Scyphozoa). Two species of comb jelly (Ctenophora) were also confirmed.

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