Plate 36 



Figure 1. Clitam'bonites hemistriatus, new species : 47 



Exterior of a pedicle valve. 



Ordovician : Near Huang-pa-yi, Shensi, China. 



2-8, 15. Pionodema pimctostriata, new species 48 



2-4, Extei'ior, posterior, and lateral views of the same 



pedicle valve. 

 5, 6, Exteriors of two pedicle valves. 

 7, 8, Exteriors of two brachial valves. 

 15, Enlarged pedicle valve (X4) of the specimen shown 



in Figure 5, showing fine punctation on the surface. 

 Formation and locality same as Figure 1. 



9. Yangtseella reticulata, new species 50 



Exterior of pedicle valve of holotype. 

 Formation and locality same as Figure 1. 



10-13. Eccyliopterus louderbacki, new species 59 



10-12, Top, umbilical, and side views of a cast of the 



holotype. 

 13, Mold of the same specimen. 

 Formation and locality same as Figure 1. 



14. Undetermined trilobite __!__ 114 



A pygidium. 



Formation and locality same as Figure 1. 



16. Cyclooeras louderhacki, new species 69 



Lateral view of the holotype with ventral outline on left. 

 Ordovician : Near Han-chung-fu, Shensi, China. 



143 



