DESCRIPTION OF PLATE n. 



Surface of slab of limestone from Locality C6, Middle Cambrian, thin platy 

 limestone in the upper shale member of the Kiu-lung group, 2.5 miles (4 km.) 

 southwest of Yen-chuang, Sin-t'ai district, Shan-tung. U. S. Nat. Mus., Cat. 

 No. 57943- 



Drepanura premesnili Bergeron [see plate 10, Liostracina krausei Monke [see plate 14, figs. 2. 2<j] 

 figs. 2, 2a-d\ (p. 129). (p. I43 ). 



1. Pygidia. 



2. Segments of the thorax. 8. Cranidium. 



3. Cranidium. 



4. Free cheek. Shantungia spinifera Walcott [see plate 14, figs. 6, 



5. Hypostoma. fi/i-/>] CD u.81 

 Agnostus douvillei Bergeron [see plate 7, figs. 3, 



30-6, 8, 8a] (p. 100). Cranidium. 



6. Pygidium. ' 



7. Cephalon. i 



230 



