| Research Abstract |
The Hina Limestone is divided into the following primitive fusulinacean zones : the Endothyra-Mediocris Zone, the Eostaffella-Millerella Zone, the Pseudostaffella-Profusulinella Zone and the Fusulinella Zone in ascending order. The Carboniferous of the Koyama Limestone can be divided into the Endothyra-Mediocris Zone, the Eostaffella-Millerella Zone, the Pseudostaffella-Profusulinella Zone and the Fusulinella Zone in ascending order. The Shimodani Limestone is divisible into the lower Endothyra-Mediocris Zone and the upper Eostaffella-Millerella Zone. The lower part of the Nakamura Limestone is regarded as the Millerella Zone containing Millerella marblensis, M.bigemmicula, Eostaffella kanmerai and smaller foraminifers. The Nagoe Formation was divided into the lower Mediocris breviscula Zone and the upper Eostaffella kanmerai-Zellerinella cf.designata Zone and the Kotani Formation cosists of the lower Pseudostaffella minuta-Millerella marblensis Zone and the upper Profusulinella toriyaamai Zone.
In the western part of the Atetsu upland we found out the primitive fusulinacean succession quite similar to that of type locality. The Taishaku Limestone is divided into six fusulinacean zones, namely, the Mediocris Zone, the Eostaffella Zone, the Millerella-Pseusostaffella minuta Zone, the Profusulinella Zone, the Fusulinella Zone and the Fusulina Zone in ascending order. We studied the fusulinacean faunas of Alaska and considered that they are of Morrowan to Atokan ages in North America.
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