FORMATIONS AND FOSSILS OF SOUTH MANGHTIBIA 



25 



Stromatocerium regulatum, new spe- 

 cies. 



Maclurites nitida (Ulrich and Sco- 

 field)? 



Maclurites higsbyi (Hall). 



Sactoceras liaotungense, new species. 

 Armenoceras asiaticum, new species. 

 Armenoceras murakamii ( Kobayashi ) . 

 Armenoceras tani (Grabau). 



WUTING FORMATION : 



Moderately thick-bedded, gray to black limestone, averaging 4 cm 

 in thickness, with interbedded thin edgewise conglomerates and dolo- 

 mitic limestone at some horizons, 160 m (524.8 feet). 



Fauna. — Annelid trails and borings; Phragmalites sp. ; and 

 Oooydiscus planulatus., new species. 



The Wuting outcrops just north of Tai-chia-pu-tzu, 2 miles west 

 of Chiao-tou station, and is faulted against the Taitzu formation. 

 Kangyao formation : 



Unfortunately, I have not yet collected any specimens from the 

 Kangyao formation in this section, but I think that it may be identi- 

 fied by future study in the field. 



CaTwdian 

 Santao formation : 



Moderately thick-bedded, light-gray to gray limestones crossed by 

 many calcite veins, with interbedded arenaceous limestones at some 

 horizons, the beds averaging 3 cm in thickness, 60 m (196.8 feet). 



Fauna. — Piloceras manchuriense, new species. 



PEN-HSI-HTJ SECTION 



On the northern rim of the Pen-hsi-hu coal field there are fine ex- 

 posures of Ordovician and Canadian strata. Here we find the type 

 localities of the Ordovician Ssuyen and Canadian Santao formations. 

 The strata from the Wuting down to the Santao form an anticlinal 

 structure just east of San-tao-kang-tzu ; while the Ssuyen dips at 

 20° or 30° to the south on the north rim of the coal field. 



Ordovician 

 Ssuyen formation: 



1. Moderately thick-bedded, gray to black limestone with many 

 calcite veins; the limestones are somewhat dolomitic in some hori- 

 zons; beds vary in thickness from 1 to 30 cm, 120 m (393.6 feet). 



There are two important fossil horizons in this formation, one 

 near the top and the other about 100 m below. 



From the upper fossil horizon: 



Camarocladia arborescens, new species. Camarocladia plana, new species. 

 Oamarocladia fucoides, new species. Maclurites biffstyi (Hall). 



