Abstract
The Chenxu Variety of Xiang features a very special tone merger phenomenon, in which some words carrying the Modern Yin-Qu tone (陰去) are inherited from the words with a voiced initial and the Ping tone (平聲) in Middle Chinese, and keep their voiced initial intact. Although the phenomenon has long been noticed, there still lacks a convincing explanation. Based on some cross-dialectical comparisons and reconstructions of sound change, it is assumed that the Chenxu Variety and the other Chinese dialects nearby had undergone some diminutive suffixation, which would make the Middle Chinese Ping tone along with voiced initials (濁平) and the Middle Chinese Qu tone accompanied by voiceless initials (清去) similar, and then induced different levels of tone merger in these dialects. In the case of Chenxu Variety, the diminutive suffix would be [n], whose suffixation not only induced tone change, but also caused the change of rime. Furthermore, the diminutive suffix [n] would come from the substrata induced by the local ethnic minorities. Finally, this study further proves that the theory of Grammaticalization Cycle (Tsao 2006) is instrumental in explaining the diminutive changes in southeastern Chinese dialects.