PLATE XVII. 



Figs. 1-9. Cynthia complanata, Herdman. 

 Figs. 10— 1G. Cynthia papietensis, n. sp. 

 Figs. 17-21. Cynthia pallida, Heller. 



Fig. 1. Cynthia complanata, seen from the right side ; natural size. 



Fig. 2. A small portion of the test of Cynthia complanata, showing the calcareous 



spicules (sp.) ; magnified (Hartn., obj. 4). 

 Fig. 3. Some of the calcareous spicules from the test, enlarged to show the arrangement 



of the echinations ; much magnified (Hartn., obj. 7). 

 Fig. 4. A small portion of the mantle, showing the musculature and the spicules ; 



magnified (Hartn., obj. 4). 

 Fig. 5. Some of these calcareous spicules (sp.) enlarged, showing the membranous sheaths 



connecting them ; much magnified (Hartn., obj. 7). 

 Fig. 6. Parts of these spicules and their sheaths ; still more magnified to show details 



(Hartn., obj. 10). 

 Fig. 7. Part of the branchial sac, seen from the inside, showing two of the folds (br.f.) 



and the interspace; magnified (Hartn., obj. 4). 

 Fig. 8. Two of the calcareous spicules from the branchial sac in the last figure ; much 



magnified (Hartn., obj. 7). 

 Fig. 9. The dorsal tubercle of Cynthia complanata, showing the convoluted course of the 



slit ; enlarged. 

 Fig. 10. A small specimen of Cynthia papiete7isis, seen from the right side ; natural size. 

 Fig. 11. A larger specimen of the same species, seen from the right side ; natural size. 

 Fig. 12. Part of the branchial sac of Cynthia papietensis, seen from the inside, showing a 



fold (brf.), an interspace, part of the dorsal lamina (I.), the dorsal tubercle 



(d.t.), and the peritubercular area; magnified (Hartn., obj. 4). 

 Fig. 13. Two of the calcareous spicules from the same branchial sac ; much magnified 



(Hartn., obj. 7). 

 Fig. 14. Part of the test of Cynthia papietensis, showing the branched vessels (v.), termi- 

 nating in knobs (t.k), and the calcareous spicules (sp.) ; magnified (Hartn., 



obj. 4). 

 Fig. 15. Three of the calcareous spicules from the test in the last figure, much enlarged to 



show the screw-nail appearance (Hartn., obj. 7). 

 Fig. 16. Part of the circle of tentacles in Cynthia papietensis, showing three orders, two 



compound (tn. and tn'.), and one simple (tn".) ; magnified (Hartn., obj. 4). 

 Fig. 17. Part of the branchial sac of Cynthia pallida, seen from the inside; magnified 



(Hartn., obj. 4). 

 Fig. 18. A small portion of the mantle of Cynthia pallida, showing the calcareous spicules 



(sp.) ; magnified (Hartn., obj. 4). 

 Fig. 19. Some of these calcareous spicules, more enlarged (Hartn., obj. 7). 

 Fig. 20. A small portion of one of the spicules, still more enlarged, to show the arrange- 

 ment of the minute echinations (Hartn., obj. 10). 

 Fig. 21. Part of the dorsal lamina of Cynthia pallida, showing the languets (I.), and the 



spicules (sp.) ; magnified (Hartn., obj. 4). 



