572 E. C. ABENDANON 



the Old Paleozoic attain a considerable development, as has been 

 pointed out by von Richthofen/ Willis,^ and others, as well as 

 myself.'' Concerning the Cambrian highland of Ordos, north of 

 the Tsing-ling-chan, we refer also to Suess (Vol. II, pp. 303 ff., 

 and Vol. Ill, Part i, pp. 252 and 263). In that part of China 

 unfolded Cambrian beds lie unconformably on folded and denuded 

 Archean formations. 



We need not go farther north, but now we return to Southern 

 China, about which Suess (Vol. Ill, Part i, p. 297) informs 

 us: "Leclere'' signale ... pres de Hoai-yuen, au Sud-Ouest de 

 Kouen-lin, une arete de terrains precambriens et un culot de 

 granite, accompagne, a I'Ouest, sur le Sikiang, par des roches 

 precambriennes." And always following Suess, we proceed back 

 again from Ta-li-fou to Cambodge, this time by the way of Yun 

 Nan, Tonkin, and Annam. According to him (Vol. Ill, Part i, 

 p. 287), the mountain chains divide. The western ones, the Bir- 

 man chains, we have followed in a zigzag way from south to north. 

 The eastern chains lead in a southeastern direction to the Cordil- 

 leras of Annam. Without entering into details, we may say that, 

 between Ta-li-fou and Indo-China, the oldest fossiliferous rocks 

 continue gradually to disappear. It is only more eastward, at 

 Lou-nan (east of Yun-nan-fou), that Leclere recognized series of 

 the Middle and the Upper Devonian, together with various forma- 

 tions of the Carboniferous and the Permian (p. 296). The tectonic 

 relation between these rocks and those of the above-mentioned 

 pre-Cambrian (also discovered by Leclere) cannot yet be estab- 

 lished. We read in Suess (Vol. Ill, Part i, p. 297) : "Les relations 

 de ces anciens terrains ne se degagent pas encore avec nettete des 

 documents publics jusqu'a present. II n'est guere possible de dire 



^ F. von Richthofen, China, 5 volumes ahd one atlas; Vol. I, 1877; Vol. II, 1882; 

 Vol. IV, 1883, atlas North China, 1885; Vols. Ill, V; and atlas, South China, 1911. 



^ B. Willis and E. Blackwelder, Research in China, 2 volumes and one atlas; 

 Vol. I, 1907. 



3 E. C. Abendanon, "La Geologie du Bassin Rouge de la province du Se-Tchouan," 

 Rev. Univ. des Mines, etc., Liege, 1906. E. C. Abendanon, "Structural Geology of 

 the Middle Yang-tzikiang Gorges," Journal of Geology, 1908. 



4 A. Leclere, "Etude geologique des provinces chinoises voisines du Tonkin," 

 Annales des Mines, 1900-1901. 



