Abstract
The "Yotsugana" Phonemic System disappeared from the Kyoto and East Japanese dialects in the late 17th century, yet the system has remained in the Kyushu dialect. At the present time, the "Yotsugana" Phonemic System is distributed in certain districts in Kyushu, and only old aged persons now use this system. These districts are Saga Prefecture, the southern part of Fukuoka Prefecture, Hita and Kusu counties of Oita Prefecture, the central and southern parts of Miyazaki Prefecture, and Satsuma Peninsula and Osumi Peninsula of Kagoshima Prefecture. The merging process of "Yotsugana" Phonemic System varies according to the phonetic environment. (1) First, the distinction between /di/;/zi/ disappears , and then the distinction between /du/;/zu/ disappears. (2) The medial affricate consonant changes into a fricative, and the initial affricate consonant remains.
