PLATE XIII. 



Iichiuocyanius pusillus, f. 1-S. 



1. Specimen seen from above, 4.74""- in diam. 



2. IMagnified portion of test showing pores along sutures, same specimen as fig. 1. 



3. Magnified portion of test, showing rosette and connection with sutural pores of same. 



4. Same specimen from actinal side. 



5. Anal plates of same. 



6. Older specimen, measuring 7.5"". in diam., showing gieater development of rosette. 



7. Section of specimen measuring 6.3""- in diam. 



8. Anal plates of fig. 6. 



Echinauthus rosaceus, f. 9. 



9. Young Echinanthus rosaceus, from above, nat. size. 



Clypeaster subdepressus, /. 10 - 18. 



10. Young Clyp. prostratus, 15.4""- in diam. from above. 



1 1 . Section showing interior edge of specimen. 



12. Magnified portion of test of fig. 10. 



13. Ambulacral petal and part of test of same. 



14. Median interambulacral edge of test of specimen measuring 21. 7""- in diam. 



1 5. Section of edge of same, showing trace of needle-like pillars. 



16. Specimen, seen from abactinal side, nat. size. 



1 7. Different specimen, showing structure of edge of test, nat. size. 



18. Same from actinal side, nat. size. The bare part of test, near the ambulacral furrows, is not 



quite distinctly enough marked in the figure. 



