(li) 12 P alxontologia Sinica Ser. B. 



was frequently met with here and there. Its upper part or the limestone bed is charac- 

 terized by the different forms of Orthochoanites and Holochoanites, and its lower part 

 or the shale bed yields the well-preserved specimens of Graptolites, Trilobites, Brachio- 

 pods and some others, but not the characteristic YangtzeeUa poloi (Martelli) which, 

 however, occurs very abundantly in western Hupeh. This formation has so far furnished 

 the following fossils : 



a. In the upper part of the Neichiashan formation. 



Endoceras grabaid Yii 



Vaginoceras (Endoceras) wahlenbergi Foord 



Vaginoceras chientzekouense Yii 



Orthoceras chinense Foord 



Orthoceras chinense Foord var. kuangchiaoense Yii 



Orthocecas chinense Food var. equiseptatum Yii 



Orthoceras cf. politum M'Coy 



Orthoceras reinotnm Yii 



Orthoceras densum Yii 



Orthoceras sp. 



Cycloceras sp. 



b. In the lower part of the Neichiashan formation. 



Didymograptus murchisoni Beck 

 Orthis calligramma Dalni. 

 Dalmanella sp. 

 Leperditia sp. 



Asaphus gigas var. hupehensis Sun 

 T aihungshania shui Sun 

 Illxnus nanchangensis Sun 

 Bathyurus minor Sun 

 Bronteus sp. 



The Geological Horizon of the So-Called Neichiashan 

 And I CHANG Formations. 



So far as we know, the upper part of the Ichang limestone belongs to the Lower 

 Ordovician, for Prof. Lee and Mr. Hsieh had collected, in beds not far from the base of over- 

 lying Neichiashan formation, some fossils, which, according to Prof. Grabau's deter- 

 mination, are of Lower Ordovician age. But the age of the lower part of Ichang forma- 

 tion already discussed by Yabe, Hsieh and others is quite uncertain. Prof. Grabau, 



