1. This report deals with the roosting flock area and flight line of the Eastern Carrion Crow and Japanese Jungle Crow living in the Zenkoji basin in the northern part of Nagano Prefecture in autumn and in winter during the years from 1963 to 1964. 2. The crows belonged to the following three roosting flock areas, Nojiri, Sanseiji and Nukazukayama, each being influenced by the lay of the land. 3. It was found that the flight line was in the lowest part of the area like a valley or above the river, making use of the natural features. 4. The roosting place of the crows in the Zenkoji basin was observed to show seasonal variation. No breeding bird's roost was observed in the breeding season, and both autumnal and winter roosts were observed in the non breeding season. 5. In the heavy snow district at the north of the Zenkoji basin, when the snow accumulated heavily and continued for a long time the winter roost was moved from Lake Nojiri to Inoue in the suburbs of Suzaka City. 6. The seasonal variation of the roosting place of crows is to be published at another occasion.
