The Nanpanjiang Limestone of eastern Yunnan has long been known as one of theimportant Devonian beds in South China.It was first proposed by Prof.Y.C.Sun in1943,and tentatively included in the upper member of the Miaokaoshan formation ofEarly Devonian age with Gypidula pseudogleata Hall as a leading fossil.Since thenmost geologists and palaeontologists have followed Sun’s assignment,while few othershave held it to be Early Middle Devonian.At the type locality near Poshi districtalong the Nanpanjiang Valley the Nanpanjiang Limestone is composed of yellowish-greyor dark grey limestone with an approximate thickness of 40—70 meters,and is overlainby the Bothriolepis-bearing beds of Lunghuashan formation.