PLATE XXXVII. 



Pentacrinus decoeus, Wyv. Thorns. 



Fig. 1. Tlip calyx aucl arm-bases of a premature individual with large 

 basals ; interradial view, ..... 



Fis:. 2. Radial view of a similar specimen with no cirri on one face of 

 the stem, . 



Fify. 3. The syzygial face of one of the distichals, 



Fig. 4. The syzygial face of a brachial. 



Fig. 5. A nodal joint from a young stem ; from the side, 



Fig. G. The lower or syzygial face of the same joint. 



Fig. 7. Side view of an infra-nodal joint from a young stem, 



Fig. 8. Its upper or syzygial face, ..... 



Fig. 9. One of the faces of an internodal joint from a young stem, . 



Fig. 10. An interpolated joint from the growing part of the stem, 



Fig. 11. The upper face of a young nodal joint from the top of 

 the stem, ....... 



Fig. 12. Its lower or syzygial face, ..... 



Fig. 13. A young internodal joint from near the top of the stem, 



Fig. 14. The upper face of a very young nodal joint witli a small inter- 

 polated joint resting upon it, . 



Fig. 15. Upper face of a young nodal joint with an interpolated joint 

 lying on it, and almost concealing it, 



Fig. 16. The lower face of the same joint, .... 



Figs. 17, 18. The lower and upper faces of a premature nodal joint. . 



Fig. 19. The upper or syzygial face of a mature infra-nodal joint, 



Fig. 20. Its lower face, ...... 



Fig. 21. The lower or syzygial face of a. mature nodal joint, . 



Fig. 22. Its upper face, ...... 



Figs. 23, 24. Portions of tlie ambulacral skeleton of two pinnules, 



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