The avian population of northern Hokkaido in the vicinity of Wakkanai was studied from April 28 to September 1, 1955. Forty nests of 16 species were found but only 13 nests were successful. Lack of success in nesting attempts resulted from disturbance by children, adverse weather, and possible predation by crows. The most abundant nesting species were those preferring low brush and dense undergrowth. During 28 days of tallying, a total of 77 species and 7074 individuals was recorded. The greatest numbers of birds were present during migration in May. Interesting species are discussed.

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A collection of bird skins from New Guinea made by Mr. Yoko-oji during 1942-1944 is here reported. The entire collection, except for 7 skins now preserved, has been destroyed by fire in 1945. Some interesting notes of collector is included.

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The author has many times investigated the distribution and breeding localities of the Chinese Hawk-Cuckoo, Cuculus fugax hyperythrus (GOULD) in Hokkaido since 1931, the result being reported in his previous paper (5). The investigation has been continued since then and the results obtained so far are given in this paper. The species commonly breeds in Honshiu, but it was not believed to occur in Hokkaido until 1930, when the first observation of this species was made in the Daisetsu Mts. by Mr. Kenzo Kobayashi (1). But, many ornithologists were still suspicious with this, because the specimen was not collected.
Since his report (5), 1949, the author has definitely ascertained that this species is quite common, and breeds in the middle and northern portions of Hokkaido. Its song exactly sounds like, "Juichi, Juichi, Juichi, ……", hence the Japanese name, "Juichi, " and by that song the author has recorded it at 15 localities in Hokkaido on the dates ranging from May 16 to July 7, as shown in Fig. 1, and the Prov. of Kitami is a new addition. Although this cuckoo is less common in Hokkaido than the Himalayan and the Japanese Cuckoos, the breeding of these three species is obvious from their occurrence during May and July.
This species is usually found in the forests of Ezo-spruce, Akaezo-spruce, Todo-fir, larch and Japanese cedar, but the author has frequently seen it in the broad-leaved trees of the above forests. Its songs, "Juichi, Juichi, Juichi…… Juk, Juk, Juk, Ju, Ju, Ju, Ju, ……" are heard during the day-time, while that of the Little Cuckoo at night or in cloudy weathers.

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Many studies on the spatial distribution of insect populations have been made by various workers. But in bird populations as well as other higher animals it is not easy to determine their spatial distribution by fitting them to a theoretical distribution. The territory mapping method, however, makes this possible.
If all individual birds seen or heard in a sample area are plotted on a map and several census trips are repeatedly made, number of groups of spots which indicate the location of the individuals and their territories will appear on a composite map. If the population density is so high that the territories are distributed all over the sample area, Neyman's type A contageous distribution with two parameters theoretically seem to realize in the spatial distribution of these spots. The observed distribu-tion obtained with respect to Emberiza spodocephala and Anthus hodgsoni apparently fitted the theoretical one.
The mean area occupied by a group of spots which is equivalent to the mean size of a territory was obtained by calculating one of the three biological constants of Neyman's type A distribution.
When, again, the population density is high and, accordingly, the distance between the nearest neighbouring territories is very short, the distribution of the territories in a sample area will be expected to be even, not random. This expectation was justified by the fact that the Poisson index of dispersion in the distribution of the geometrical centres of territories was always smaller than 1. The index, however, was not always significantly different from 1. This means that the distribution of territories in high population density would be essentially even, but, in some cases, the Poisson type apparently appeared as a result of unevenness of the environment which probably disturbed the even distribution of the territories.

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The Japanese Scops Owl has been considered a summer bird. The author obtained a fresh dead specimen on 31 December, 1956, which was caught alive the day before at Shimo-Ome, Tokyo. Its stomach contained a moth-like insect and two ants.A second bird was observed also in Ome, 13 December, 1957. These two records may suggest that this species winters in Japan.

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The Scops Owl, being a small sized species, feeds almost exclusively on insects. Oka's two December records should be unhealthy birds which remained until early winter. There may be a probability of its wintering in warmer parts in Japan, such as Amami-Oshima as given in the Hand-list (1958), where food insects are to be found in this season. But, the author rather believes, as mentioned by Yamashina (1931), that it is a summer migrant, because La Touche reports it as winter bird from central and southern parts of E. China.

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