(0 10 Palxontologia Sinica Scr. B 



Shales and slialy limestones, yellowish gray to violet 79m. 



Brownish and red limestone conglomerate 5m. 



Platey limestone 17 m. 



Interstratified sill 7 m. 



Shales and slialy limestones 22 m. 



Limestone 5m. 



Brown shales and calcarenytes 13 m. 



Brownish-red limestone conglomerate 1 m. 



Pettintze formation (exposed) 95m. 



Oolitic limestone 23 m. 



Bluish black massive limestone with fossil horizons F2, 10 meters and Fl, 



33 meters below the top 72m. 



Base not exposed 



Total exposed thickness of Ordovician 525m. 



The most significant fact revealed by the study of this section is the absence of 

 the Machiakou or Actinoceras limestone, which over such a wide area directly underlies 

 the Carboniferous formations. This indicates a very pronounced pre-Carboniferous 

 erosion in this region and further, a marked irregularity of attitude of the Ordovician 

 strata, for a short distance to the south the higher limestones are present, and they are 

 again found further to the north in Manchuria. 



PEILINTZE LIMESTONE. A noteworthy fact is the apparent entire distinctness 

 of the two faunas found in the limestones of this section. The fauna of the lower or 

 Peilinfze limestone at present comprises the following species: 



ACTINOZOA (?) 



1 Archii'ocyathns (Arclxoscyphia) chihliense Grabau 

 GASTROPODA 



2 Ophileta squamosa Grabau 



3 Fasispira sp. 



CEPHALOPODA 



4 Protocameroceras mattJiieui Grabau 



5 Chihlioceras nathani Grabau 



6 Chihlioceras chingtuangtaoense Grabau 



? 7 Piloceras platyventmm Grabau (doubtful from this horizon). 



The presence of Archd'ocyathus in this fauna is noteworthy. This genus, and 

 indeed all of the Archieocyathinic, are typical of Cambrian horizons, occurring most 



