Fig. I 



Plate XII. 



Valve of tridentate pedicellaria of Phormosoma biirsarinm. Obj. II. Oc. I. 



— 2. — - — — - — placenta^ from the Davis Strait. Obj. II. Oc. o. 



— 3. — - — — - — — — the Gulf of Mexico. Obj. II. Oc. o. 



— 4. Developmental stage of a large tridentate pedicellaria of Phormosoma placenta. Obj. II. Oc. o. 



— 5. Valve of a half developed — ^ — — - — — Obj. II. Oc. o. 



— 6. — — tridentate pedicellaria of Phormosoma rigidum. Obj. II. Oc. I. 



— 7. — — — — - — placenta (Ingolf. St. 40). Obj. II. Oc. o. 



— 8—10. Transverse sections of the head of a globiferous pedicellaria of Hapalosoma pelhicidum. 



8. nearest to the basis, 10. in the middle, 9. at the point. Obj. II. Oc. III. 



— II. Actinal primary spine of Phormosoma placenta., the bag of skin removed. Obj. 00. Oc. o. 



— 12. Valve of a triphyllous pedicellaria of Kamptosoma asterias. Obj. II. Oc. III. 



— 13. — — — — - v-Asthenos. gracile^ (Chall. St. 219). Obj II. Oc. III. 



— 14. — — — — - Hapalosoma pelluciditm. Obj. II. Oc. III. 



— 15. Developmental stage of a triiDhyllous pedicellaria of Phormosoma placejita. Obj. II. Oc. I. 



— 16. Valve of a triphyllous pedicellaria of Aperosoma Grimaldii. Obj. II. Oc. I. 



— 17. — — — — - EchtJiosoma nranits. Obj. II. Oc. I. 



— 18. — — — — - Asthenosoma -variiim. Obj. II. Oc. III. 



— 19. Spine from the peristome of Phormosoma placenta; with bag of skin. Obj. o. Oc. o. 



— 20. Valve of a triphyllous pedicellaria of Hygrosoma liiculentiun. Obj. II. Oc. I. 



— 21. — — — — - Phormosoma placenta. Obj II. Oc. I. 



— 22. — — tridentate — small form, of Tromikosoina Koehleri. Obj. II. Oc. o. 



— 23. Sphseridia of Phormosoma placenta. Obj. II. Oc. I. 



— 24. Developmental stage of a triphyllous pedicellaria of Phormosoma placejita. Obj. II. Oc. I. 



— 25. Sphseridia of Phormosoma placenta. Obj. II. Oc. I. 



— 26. Valve of a small tridentate pedicellaria of Phormosoma placenta. Obj. II. Oc. o. 



— 27. — — triphyllous pedicellaria of Arceosoma coriacetun. Obj. II. Oc. I. 



— 28. — — — — - Phormosoma hirsarium. Obj. II. Oc. I. 



— 29. — — — — - Arceosoma Belli. Obj. II. Oc. I. 



— 30. Developmental stage of a triphyllous pedicellaria of Phormosoma placenta. Obj. II. Oc. I. 



— 31. Valve of a triphyllous pedicellaria of Tromikosoma Koehleri. Obj. II. Oc. I. 



— 32. — — — ' — - Kamptosoma asterias [<!. Phormosoma tenue^^., Chall. St. 272). 



Obj. II. Oc. III. 



— Z2)- Valve of a triph)llous — - Arceosoma fenestratum. Obj. II. Oc. I. 



— 34. — — — — - Calveria hystrix. Obj. II. Oc. III. 



— 35. — — large tridentate pedicellaria of Echinosoma temce., seen half from the side. Obj. o. Oc. o. 



— 36. — — tridentate — - — tiranus. Obj. II. Oc. I. 



— 37 and 39. Valve of a small tridentate pedicellaria of Phormosoma placenta. Obj. II. Oc. o. The 



edge finely serrate, which cannot be seen under the magnifying powers used in the drawing. 



— 38. Valve of a half developed triphyllous pedicellaria of Phormosoma placenta. Obj. II. Oc. I. 



— 40. — — small tridentate pedicellaria of Echinosotna tenue. Obj. II. Oc. o. 



— 41. — — large — — - Tromikosoma Koehleri. Obj. o. Oc. o. 



— 42. — — triphyllous pedicellaria of Hygrosoma Petersii. Obj. II. Oc. I. 



