DESCRIPTION OF PLATE 10. 



Damesella blackwelderi Walcott (p. 125). 



1. Cranidium drawn from three imperfect specimens. Natural size. U. S. Nat. Mus., Cat. No. 57920. 



10. Associated free cheek. U. S. Nat. Mus., Cat. No. 57921. 



ib. Outline of side view of specimen represented by fig. i. U. S. Nat. Mus., Cat. No. 57920. 



i c. Cranidium with more coarsely granulated surface. Natural size. From Locality C 13 (same general 



locality as 12), Middle Cambrian, Kiu-lung group, yellow slabby limestone 6 miles (9.6 km.) 



southwest of Yen-chuang, Shan-tung. U. S. Nat. Mus., Cat. No. 57922. 



id. Free cheek associated with head represented by fig. ic. U. S. Nat. Mus., Cat. No. 57923. 

 je. Pygidium associated. U. S. Nat. Mus., Cat. No. 57924. 

 i/. Pygidium associated. U. S. Nat. Mus., Cat. No. 57925. 

 ig. Thoracic segment associated. U. S. Nat. Mus., Cat. No. 57926. 

 i A. Interior of head and thorax. Natural size. From Locality 014 (same general locality as C 12), 



Middle Cambrian, Kiu-lung group, southwest of Yen-chuang, Shan-tung. U. S. Nat. Mus., 



Cat. No. 57928. 



11. Hypostoma associated. U. S. Nat. Mus., Cat. No. 57929. 



U- Pygidium with very strong spines, associated with fig. i. U. S. Nat. Mus., Cat. No. 57927. 



All of the specimens illustrated, except those represented by figs, ic, id, and ih, are from Locality 

 C 12, Middle Cambrian, Kiu-lung group, southwest of Yen-chuang, Shan-tung. 



Drepanura premesnili Bergeron [see plate n, figs. 1-5] (p. 129). 



2. Top and side views of a typical form of the cranidium. From Locality 055, Middle Cambrian, 



Ch'au-mi-tien limestone, south 80 east of Tsi-nan, Shan-tung. U. S. Nat. Mus., Cat. No. 



57932- 



20. Associated free cheek, X 2. U. S. Nat. Mus., Cat. No. 57933. 

 26 and ic. Typical forms of the pygidium, 26 X 2; 2C natural size. U. S. Nat. Mus., Cat. Nos. 57934 



and 57935- 

 2d. Two thoracic segments showing part of axial lobe and pleural lobe, X 1.5. U. S. Nat. Mus., Cat. 



No. 57936. 



The specimens represented by figs. 2a-d are from Locality 06, Middle Cambrian, Kiu-lung group, 

 southwest of Yen-chuang, Shan-tung. 



2e. Associated hypostoma referred to this species, X 3. (06.) U. S. Nat. Mus., Cat. No. 57937. 

 Drepanura ketteleri Monke (p. 129). 



3. Central parts of the cephalon, X 3. From Locality 055, Middle Cambrian, Ch'au-mi-tien, east of 



Tsi-nan, Shan-tung. U. S. Nat. Mus., Cat. No. 57939. 

 30 and 30. Small pygidia enlarged, X 7. Associated with fig. 3. U. S. Nat. Mus., Cat. Nos. 57940 



and 5794 1. 

 36. View of under side of a small pygidium, X 5. From Locality C 6, Middle Cambrian, Kiu-lung group, 



2.5 miles (4 km.) southwest of Yen-chuang, Shan-tung. U. S. Nat. Mus., Cat. No. 57942. 



248 



