73 



above and second, on the following stratigraphical account given by 

 Blackwelder ; 



" Nan-tou formation is limited above by an uneven surface, upon which 

 lies a thin sheet of conglomerate. The matrix of the conglomerate is a 

 greenish ai gillaceous limestone and the pebbles are like those in the under- 

 lying tillite. The two formations are therefore related by a basal conglomerate, 

 which the till was well calcurated to furnish.'' " 



The true nature of a red formation such as Manto shale is a sub- 

 ject to be variously interpreted ; at least, it is to me not quite sure, that the 

 Man-to sea was inhabited by a limited number of shore organisms owing to 

 the cold temperature, for the equiv^alent red shale (with Rcdlicliia cliiiicnsis) 

 in Manchuria and Korea is found sometimes full of the tests of trilobites and 

 brachiopods in its particular zone, which is in itself red shale and non- 

 calcareous. 



At present, we know two reported cases of Cambrian glacial deposits, 

 one of which is Nan-tou tillite now we concern and the o'.her the extensi\'e 

 tiUite developed in the Adelaid district of South Australia. As to the latter, 

 it was sometimes interpreted as of Vve-Olciic/iis age ; according to Noeiling,"' 

 however, it is not quite excluded that the boundary between the tillite and 

 the overlying Cambrian quartzite is simpl)' deceptive, the present condition 

 being brought to existence by a subsequent tectonic disturbance. As the 

 Cambrian glaciation is thus yet established nowhere in the world, I feel 

 warranted to express on behalf of safety that it is premature to assign Lower 

 Cambrian age to the Nan-tou tiUite. 



The b. marl layer in the Upper Clayslate series of Noda contains the 

 fossils described above at Pan-tse-}'a (Hu-hsi) and Kao-huang-ling, which in- 

 dicate without doubt the Upper Ordovician age of the marl layer. The same 

 bed exposed along the Yang-tse-kiang near Sin-tan did not afford any fossils 

 to Noda ; but E. C. Abendanon''' succeeded in collecting a fine lot of fossils in 

 a limestone bed quite near the spot. This collection was studied by Fkech 



1) Research in China, vol. I., r, p. /6g. 



2) F NoETi.iNG: L'eber Glazialschichten angeblich cambrischen Alters in Siid-Australien. 

 Geol. u Pal. Abh., N.F., Bd. XL, igi2. 



3) Akendanon': Structural Geology of the Middle Yang-tse-kiang Gorges. Journal Geol., vol. 

 XVI., rgoS. 



