Distribution of the freshwater unionid mussels were investigated at twentythree localities of five river systems in Kanagawa Prefecture from September 2004 to September 2009. Five species, Unio douglasiae nipponensis, Inversiunio jokohamensis, Pronodularia japanensis, Anodonta "woodiana" (which encompasses A. japonica and A. lanta) and A. calipygos were recorded from thirteen localities. It is noteworthy that living individuals of U. douglasiae nipponensis were found at the midstream area of the Sagamigawa River accompanied by A. spp., which is the first record for this species at this river system. Living mussels including glochidia of both I. jokohamensis and P. japanensis were collected from the branch of the Sakaigawa River. Some living individuals and many dead shells of A. "woodiana" were collected from eleven localities. Glochidia and juveniles of this species also found on the body surfaces of the fishes caught by dip net at the pond nearby the Sagamigawa River.

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A giant gall was collected on the living trunk of Styrax japonica, at Odawara of Kanagawa Prefecture, Honshu, Japan, on 13 January 2009. It was determined as the gall produced by the primary-host generation of the aphid, Tuberaphis takenouchii. As a result of continuous observation of secondary-host candicate, Scurrula yadoriki at adjacent area, we detected the leafgalls of S. yadoriki at the point 9.5km apart from the above mentioned locality in Odawara, on 31 July. 2009. It was identified by Dr. S. Aoki as the gall produced by the secondary-host generation of the species. This is the first record of the secondary-host generation of T. takenouchii in Japan.

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Occurrences of basking shark, Cetorhinus maximus (Gunnerus, 1765) (Lamniformes: Cetorhinidae) in Sagami Bay were reviewed. There are three certain records of this species in the bay: an individual fished off Enoshima in March 21, 1961, a female of about 4 m in total length fished off Sajima in June 8, 2005, and a male of 4.74 m in total length fished off Chojagasaki in April 26, 2009. These fishes were captured with a set-net, and immature in all cases. When we analyzed sea conditions of April 24 to 27, it was suggested that occurrence of Chojagasaki's specimen is no relation to the Oyashio Current. We presumed that this species strayed accidentally into the bay because of extremely low frequency of occurrence.

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We investigated the fish fauna at 40 stations in the mainstream and 13 tributraries of the Sagami River system. As the result, 42 species belonging to 15 families collected. They comprised 29 genuine freshwater, 11 diadromous and 2 peripheral freshwater species. Of genuine freshwater species, the number of domestic alien species is more than those of the native. The fish species occurred in high frequency were in order of Phoxinus lagowskii steindachneri, Oncorhynchus masou masou, Tribolodon hakonensis, Cobitis biwae, Rhinogobius sp. OR and Zacco platypus. Larger tributary has high diversity in the number of species, and the number exceeds those of the mainstream. They were in order of the Koayu River, Nagaike River and Tama River.

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The authors analized the stomach contents of two Japanese black bears which were caught in Tanzawa mountains, Kanagawa. One stomach contains leaves, stalks, and roots of genus Arisaema. Another one contains parts of the first stomach and the skin of a certain ruminant, and several plant parts (leaves, seeds, and broken piece of walnut shells). These results suggest the human impact on the food habits of Japanese black bears in Tanzawa mountains.

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