LECTURE VI. 



On Corals and Crinoidea. 



1. Introductory. 2. Organic and Inorganic Bodies. 3. Distinction between 

 Animals and Vegetables. 4. Nervous System and Sensation. 5. Diversity of 

 Animal Forms. 6. Animal nature of Zoophytes. 7. Cilia, or vibratile Organs. 

 8. Hydrse, or Fresh-water Polypes. 9. Elementary organic Structure. 10. Ana- 

 logy not Identity. 11. The Flustrae. 12. Food of Zoophytes. 13. Nature of 

 Coral Zoophytes. 14. Corals, or Polyparia. 15. Geographical distribution of 

 Corals. 16. Sertularise, or Vesicular Corallines. 17. The Gorgonia. 18. The 

 Red Coral. 19. Tubipora, or Organ-pipe Coral. 20. Madrepores. 21. The 

 Actinia,or Sea-Anemone. 22. CaryophylliaandTurbinolia. 23. Fungia. 24. Astraea 

 and Pavonia. 25. Meandrina, or Brain Coral. 26. Appearance of living Corals. 

 27. Coral Reefs. 28. Coral Reef of Loo-Choo. 29. Coral Islands. 30. Formation 

 of Coral Islands. 31. Montgomery on Coral Islands. 32. Fossil Zoophytes. 

 33. Ventriculites. 34. Zoophytes of the Oolite and Lias. 35. Corals of the 

 Palaeozoic Formations. 36. Coralline Marbles. 37. The Crinoidea. 38. Structure 

 of the Crinoidea. 39. Encrinites and Pentacrinites. 40. Derbyshire Encrinital 

 Marble. 41. The Lily Encrinite. 42. Pear Encrinite of Bradford. 43. Penta- 

 crinites and Actinocrinites. 44. Pentremites and Cystidea. 45. Concluding 

 Remarks. 



1. Introductory. — In many of the deposits of the Secon- 

 dary formations reviewed in the last discourse, a large 

 proportion of the fossils consisted of those interesting types 

 of animal organization, the Polyparia, Crinoidea, and other 

 zoophytes : some of the oolitic strata, as for example the 

 Coral-rag, being wholly made up of corals ; while many of 

 the limestones and shales of the Lias, equally abounded in 

 Encrinites, Pentacrinites, and other forms of the Crinoidea. 

 In the more ancient palaeozoic formations, to the examina- 

 tion of which our attention will hereafter be directed, we 

 shall find these organisms in still greater profusion ; entire 

 mountain chains consisting of the consolidated remains of 

 corals, and vast tracts, of limestones composed of the mine- 

 ralized skeletons of the Lily-shaped animals. 



