122 



PBOCEEDINGS OF THE GEOLOGICAL SOCIETY. [DoC. 23, 



River, a tributary of the former flowing past Kweilin-fu, the capital 

 of Kwangsi province. In the valley of Modo, near Soochow, in 

 Kiangsu, a fine section is also exposed. The Lu-shan, a fine range 

 of mountains near Kiukiang, commanding the entrance to the 

 Poyang lake, is likewise composed of these rocks, which, more- 

 over, appear at intervals through the entire district south of the 

 Yangtse. In the island of Hongkong, and stretching along the 

 sea-coast as far as the Chusan archipelago, they, much altered 

 and associated with igneous rocks of various descriptions, form 

 the main portion of the coast-range. Even in Hongkong itself an 

 attentive examination discovers these slate rocks, but entangled 

 with at least two series of plutonic rocks — one granitic, the other 

 trachytic, and both evidently posterior to the sedimentary rocks. 

 Near Soochow, likewise, in the Modo valley spoken of above, a mass 

 of reddish granite rises from the midst of the lower shales, towards 

 the axis of which the surrounding strata dip. 



Pig. 2.- 



S.S.E. 



White Deer Wu-lao-feng The Lu-Shan 

 Grotto. „(4.500feet\ (5040 feet). 



Section of the Kiuhiang district, Kiangsu. 

 (Scale 6 miles to 1 inch.) 



Tien Chi 

 Pagoda. 



N.N.W. 



Fossils. 



Granite. 



Tungting G-rits. 



Lime- 

 stones. 

 1 Quartzites. 2. Soft shales and schists. 



a. Soft schists, converted into mica-schist and gneiss. 



b. Limestone overlain by the Kiukiang laterite, with a base of coarse till con- 



taining small boulders. 



At the Lu-shan the subsequent origin of the igneous rocks is also 

 well displayed in the conversion of a portion of the superincumbent 

 shales into mica-schist and gneiss ; in Lower Kiangsu, likewise, the 

 detached hills which appear over the surface of the alluvial plain are 

 composed of the remains of these quartzites preserved from the de- 

 nudation which destroyed the other portions of the series by the 

 hardening effect of the intrusion of a series of porphyritic dykes 

 having a general direction from "W.S.W. to E.N.E. 



Lying, as above stated, conformably over the Tungting grits, is a 

 great mass of limestone, containing near its base, in the central pro- 

 vinces at least, a mass of shales of no great thickness producing coal 

 and iron. Throughout the valley of the Yangtse, from the Taihu in 

 Kiangsu westwards to the province of Hupeh, I have traced the lower 

 bed, No. 4, of the series. This bed where exposed is rendered very 

 conspicuous from projecting nodules of black chert jutting out far 

 beyond the water-worn and often honeycombed limestone matrix ; 

 in fact one of the chief features of the series in the provinces of 

 Kwangtung and Kwangsi is the extraordinary extent to which the 

 solvent power of water has acted on the rock. In the valley of the 



