Plate 26 



Page 



Figure 1. Bathyurus (?) species undetermined 110 



Dorsal view of a pygidium. 



Lower Ordovician, Wuting formation : In the gray lime- 

 stone near Pen-hsi-hu, Liao-tung, Manchuria. 



2-6. Undetermined trilobite 114 



2-4, Three pygidia, which seem to belong to the same species. 



5, An associated free cheek. 



6, A pygidium, belonging to a different species. 



Lo\\er Ordovician, Wuting formation : Limestone beds en 

 the top of the Wu-ting-shan, south of Yen-tai, Liao-tung, 

 Manchuria. 



7, 8. Helicotoma species undetermined 60 



Top and side views of a specimen. 

 Formation and locality same as preceding. 

 9, 10. Nybyoceras foerstei Endo 79 



9, Top segment of the specimen shown on Plate 25, Figures 



3-5, viewed from above, showing location and size of 

 siphuncle. 



10. A dorsal view of the same specimen. 



11. Armenoceras numatai, new species 94 



Specimen weathered out on dorsal side, exposing the 



siphuncle. (See also pi. 40, fig. 7.) 

 Formation and locality same as Figure 1. 



133 



