On the strata and development of yu 鱼 rhyme category in Southern Wu dialects

There are scholars who have already done some research on the sound strata of Yu 鱼rhyme in Southern Wu dialects such as Mei Zulin (2001) and Chen Zhongmin (2013). Accordingly, this article presents a further research, which has found eight sound strata of Yu 鱼 rhyme in Southern Wu dialects. Layer I merges into the Yu 鱼 and Ma麻 rhymes. Layer II is that Yu 鱼 rhyme stands alone. Layer III merges into the Yu 鱼 and Hou 侯 rhymes. Layer IV and V are both Yu 鱼 and Zhi 支 rhymes, sharing the same pronunciation. Layer V is the result of some dropping medials from Layer IV. Layer VI includes the Yu 鱼 Zhi 支 Zhi脂 Zhi 之 and Wei 微 rhymes. Layer VI with high vowels becomes layer VII. Layer VIII consists of Yu 鱼 and Yu 虞 rhymes. Layer I originated in Western Han Dynasty, layers II, III, IV, V, VI and VII resulted from changes of Yu 鱼 rhyme in Six Dynasties (Wei Jin Nan Bei Chao), and layer VIII is from the late Tang period to Five Dynasties and Ten Kingdoms (Wu Dai Shi Guo) period. The article also discusses the ways to distinguish between the cognate stratum and the heterogeneous stratum. Layers I, II, III, IV, V, VI and VII are all cognate strata from lexical diffusion of the evolution in Southern Wu dialects while layer VIII is a heterogeneous stratum. Meanwhile, this article has reconstructed the process of cognate strata change.