PLATE IX. 



ClDARIS TEHAMAENSIS Clark, 11. Sp. (p. 44). 



U. S. Nat. Mus. 31195, type. 

 Figure 1. Lateral view of spine. 



Cidaris texanus Clark (p. 45). 



U. S. Nat. Mus. 8381, type. 

 Figure 2a. Test, natural size. 



2b. Test, restored, slightly enlarged. 



2c. Arrangement of the interambulacral plates in the vicinity of the apical disk, with adjacent ambulacral 



plates. Slightly enlarged. 

 2d. Portion of ambulacrum, X 6. 

 2e. Interambulacral plate, slightly enlarged. 

 2f. Tubercle, X 3. 



Cidaris walcotti Clark (p. 45). 



Acad. Nat. Sci. Philadelphia 1451, type. 



Figure 3a. Portion of the test. 



3b. Interambulacral plates, X 2. 

 3c. Portion of ambulacrum, X 8. 

 3d. Tubercle, X 4. 



Cidaris splendens Morton (p. 46). 

 Johns Hopkins Univ. T 3001. 



Figure 4a. Upper surface of the test. 

 4b. Lateral surface of the test. 



Cidaris splendens Morton (p. 46). 

 Acad. Nat. Sci. Philadelphia, type. 



Figure 5a. Portion of test. 



5b. Interambulacral plate, X 2. 

 5c. Portion of ambulacral area, X 5. 

 5d. Tubercle, lateral view, X 2. 

 5e. Spine, X 2. 

 5f. Base of same, X 6. 



Figure 6. Genital plate. 



Cidaris splendens Morton (p. 46). 

 Johns Hopkins Univ. T 3002. 



Cidaris dixiensis Clark, n. sp. (p. 47). 

 Geol. Survey Texas, type. 



Figure 7a. Interambulacral plate. 

 7b. Same. 

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