Devonian Strata of the Nandan Type at Nandan of Northern Guangxi with Special Referance to Planktonic and Nektonic Faunas Ruan Yiping and Mu Daocheng Devonian Tentaculites from Luofu of Nandan,Northern Guangxi Mu Daocheng and Ruan Yiping Ostracods from the Devonian Sipai Formation of Guangxi Wang Shangqi Ostracods from the Early Devonian Ertang Formation of Guangxi Wang Shangqi