ORDOVICIAN SYSTEM : NAUNGKANGYI STAGE. 



117 



only those genera and species which have a world-wide distribution 

 are common to the two areas. 



The existence of strata of Ordovician age in Yunnan was first 

 „ . brought to light by v. Loczy, who has de- 



Extension into Yunnan. . ° °. J J 



scribed them in the account of the expedition 



of Graf Bela Szechenyi to China (1877-1880). 1 The locality is 



situated at Pu-pjao, on the eastern side of the Salween river, on the 



road from Teng-yueh to Ta-li-fu, and the beds consist of slaty shales 



of various colours. The only fossils found by v. Loczy were some 



cystidean plates referred doubtfully to Hemicosmites, similar to 



those which are so common in the Naungkangyi beds, and are 



supposed by Mr. Cowper Reed to belong to Carfpcrinus, 2 and 



very imperfect remains of trilobites ; but the locality has more 



recently been visited by Mr. Coggin Brown, who is convinced that 



the Pu-pjao beds are identical with the Naungkangyi formation of 



the Shan States, and has collected a rich fauna, consisting of 



brachiopods and trilobites, and above all of graptolites, including 



well preserved specimens of Didymograptiis, which, it is to be 



hoped, will go far in enabling the true horizon of the beds to be 



established, when their affinities have been worked out. As will 



be seen below, this is the third distinct graptolite horizon that has 



hitherto been discovered in south-eastern Asia. In addition to 



confirming v. Loczy's observation, Mr. Coggin Brown has also 



obtained, from a locality further to the south, a fine series of 



Cystideans, resembling in their mode of preservation and other 



characters the peculiar forms of Sedaw in the Shan States. His 



collections are now in the hands of Mr. Cowper Reed, and it is 



anticipated that a description of them will soon be ready for 



publication. 



A wide interval separates these localities in Yunnan from the 

 Equivalents in Cen- representatives of Ordovician strata described 

 tral and North Eastern by v. Richthofen, Bailey Willis, and others 3 

 china " as occurring in Central and north-eastern 



China. The formation there constitutes the upper part of the 



1 Roise doe Grafon Bela Szechenyi in Ostasien, Vol. I, p. 707 ; Vol. Ill, p. 21. 

 ■ Op. cit., Pal. Ind., New Ser., Vol. II, Mem. No. 3, p. 33. 



» v. Richthofen. China, Vol. II. pp. 22<i, :t I !> : Bailey Willis, Research in China, 

 Vol. I, Pt. 1, pp. 43, 2ti!» ; Vol. II, p. 42 : T. Lorenz, Op. cit., Zeitachr. d. lkvlsch. Gtol. 

 Geaellsch. Bd. LV11, p. 447. In Bd. 1A III. Lorenz urns, on pp. 116 to 119, a useful 

 summary of our knowledge of the Palaeozoic formations of China and the neighbour- 

 ing regions, to tho year l!t().j : F. Leprinec-Rinj'Uet, Etude C« oloL'icpie sur le. Kord de la 

 Chine; Annules dea Mines, Ser. Vol. XIX, p. 347, a rieuml of v. Richthofen 't 



