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. 
1a. Associated free cheek. U.S. Nat. Mus., Cat. No. 57921. 
1b. Outline of side view of specimen represented by fig. 1. U.S. Nat. Mus., Cat. No. 57920. 
1c. Cranidium with more coarsely granulated surface. Naturalsize. From Locality C 13 (same general 
locality as C12), 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. 
1d. Free cheek associated with head represented by fig. 1c. U.S. Nat. Mus., Cat. No. 57923. 
re. Pygidium associated. U.S. Nat. Mus., Cat. No. 57924. 
if. Pygidium associated. U. S. Nat. Mus., Cat. No. 57925. 
1g. Thoracic segment associated. U.S. Nat. Mus., Cat. No. 57926. 
th. Interior of head and thorax. Natural size. From Locality C14 (same general locality as C12), 
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. 
1j. Pygidium with very strong spines, associated with fig. 1. U.S. Nat. Mus., Cat. No. 57927. 
All of the specimens illustrated, except those represented by figs. 1c, 1d, and 1h, are from Locality 
C12, Middle Cambrian, Kiu-lung group, southwest of Yen-chuang, Shan-tung. 
Drepanura premesnili Bergeron [see plate 11, figs. 1-5] (p. 129). 
2. Top and side views of a typical form of the cranidium. From Locality C55, Middle Cambrian, 
Ch’au-mi-tién limestone, south 80° east of Tsi-nan, Shan-tung. U.S. Nat. Mus., Cat. No. 
57932. 
2a. Associated free cheek, X 2. U.S. Nat. Mus., Cat. No. 57933. 
2b and 2c. Typical forms of the pygidium, 2b 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 C6, Middle Cambrian, Kiu-lung group, 
southwest of Yen-chuang, Shan-tung. 
2e. Associated hypostoma referred to this species, X 3. (C6.) U.S. Nat. Mus., Cat. No. 57937. 
Drepanura ketteleri Monke (p. 129). 
3. Central parts of the cephalon, X 3. From Locality C55, Middle Cambrian, Ch’au-mi-tién, east of 
Tsi-nan, Shan-tung. U.S. Nat. Mus., Cat. No. 57939. 
3a and 3c. Small pygidia enlarged, X 7. Associated with fig. 3. U.S. Nat. Mus., Cat. Nos. 57940 
and 57941. 
3b. View of under side of a small pygidium, X 5. From Locality C6, Middle Cambrian, Kiu-lung group, 
2.5 miles (4 km.) southwest of Yen-chuang, Shan-tung. U.S. Nat. Mus., Cat. No. 57942. 
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