1) Some strange objects, shells, glass, plastic, porcelain, etc., were found from the nests of Broad-billed Rollers Eurystomus orientalis. These objects had some common characteristics; most of them had a hard and shiny surface, and had no nutritional value.
2) Using experiments with test objects, we examined when and where these objects were brought to the nest. The experiments showed that most objects were brought to the nests from less than 200 m away.
3) Strange objects were brought to the nests mainly at the end of the nestling and copulation period (the most frequent time of feeding). The test objects brought during the copulation period were found both in the area near nest and under nests, while the test objects collected during the nestling perod were from the bottom of nests.
4) Most objects (80.6%) collected from the bottom of nests and 41.8% of the objects collected from under the nests were very dirty with small fragments of chitinous parts of insects. The average size of clean objects was larger than that of the dirty objects.
5) Some of the test objects removed by Broad-billed Rollers were found to have been folded. All of the deformed test objects were very dirty.
6) Most of the dirty aluminium pieces had some scratches on the surface. The aluminium pieces used by Broad-billed Rollers had some scratches on the outer surface, however, there were no scratches on the inner surfaces.
7) It was shown that the dirty objects were swallowed by nestlings or parent birds and then regurgitated as pellets, and the scratches left on the surface of the aluminium objects were made by the objects being rubbed together in the bird's stomach. From these observations, it was concluded that the strange objects were used as "millstones" for grinding hard chitinous bodies of beetles, which are main food of Broad-billed Rollers, and to aid digestion.
8) The possibility that the objects brought at the nests during the copulation period were used as a tool of courtship display was also discussed.

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Breeding bird communities were investigated in the lower montane zone in southern Kyushu Two areas were studied which have the mixed forest of evergreen broad-leaved and coniferou plantation (A) and agricultural land with a patchy mixture of young plantations (B) in the surroundings of Mt. Eboshi (alt. 522 m) near Kagoshima City. Twenty eight species were ob served in area A and 24 in area B, with 20 species common to both areas. Four species hac greater relative densities in area A than area B, and nine species showed the reverse pattern The bird community in area A was composed of a Hypsipetes amaurotis-Parus major-Aegithalos, caudatus-Parus varius association and in area B of a H. amaurotis-Passer montanus-Cettia diphone-Emberiza cioides association. The rank correlation coefficient between area A anc Kirishima (KURODA et al. 1972) was high in relation to both avifauna. The breeding bird corn munity, with a high density of H. amaurotis and low densities of certain typical woodlanc species, such as Ficedula narcissina, Cyanoptila cyanomelana, seems to be the result of the habita being composed of a high proportion of coniferous plantation and young broad-leaved secondar3 forest mixed with plantation

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The feeding behaviour of 6 species of the Charadriidae and 19 species of the Scolopacidae was investigated during the spring and fall migration periods in 1985 at Kubiki Plain, Niigata Prefecture, central Japan. Pacing and pecking rates were recorded. The frequencies of pacing and pecking were compared between the different species and in different environments. 1) The Scolopacidae were found to peck continously while walking, but the Charadriidae stopped many times while pecking.
2) The lighter species of the Charadriidae and Scolopacidae tended to peck more rapidly than the larger and heavier species did.
3) In the Charadriidae peck rates were slower than in the Scolopacidae, and the variation among the Charadriidae in relation to the frequencies of walking steps was larger than the variation of frequencies of pecks, both during the spring and fall migration periods.
4) In the Scolopacidae, peck rates were faster than in the Charadriidae and the variation of peck rates among species was very large.
5) When Calidris alpina and Limicola falcinellus entered shallow water, they tended to probe in stead of pecking. The number of steps decreased from that recorded on wet mud because probing took longer than pecking.
6) Members of the Scolopacidae and Charadriidae are ecologically separated by means of two adaptive trends. In the Scolopacidae, the trend is towards greater variation in the morphology and greater diversity in the use of the bill, while the trend in the Charadriidae is towards greater variation in the pace length which is related to the leg length. That is, the Scolopacidae are specialists in relation to bill usage, while the Charadriidae are generalists in relation to bill usage.

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