Plate 52. 

 1-7. Salenocidaris crassispina A. Ag. and CL 



1. Actinal view of denuded test, x 10. 



2. Abactinal view of same. X 10. 



3. Left anterior ambulacrum, x 10. 



4. Right posterior interambulacrum. x 10. 



5. Primary spine. X 4. 



6. Base of primary spine, x 8. 



7. Tip of primary spine, x 8. 



8-13. Salenia cincta A. Ag. and CL 



8. Actinal view of denuded test, x 4. 



9. Abactinal view of same, x 4. 



10. Odd anterior ambulacrum, x 4. 



11. Left posterior interambulacrum. x 4. 



12. Base of primary spine, x 4. 



13. Tip of primary spine, x 4. 



