we see forms of animated existence, possessing faculties and sensations wholly dissimilar to our own; and while, in the beautiful language of Scripture, we are told that not a sparrow falls to the ground without our heavenly Father's notice, the contemplation of the present constitution of nature, by any philosophical observer, would alike condemn such vanity and presumption. For my own part, feeling, as I do, the most profound reverence, and the deepest gratitude to the Eternal, who has given unto me this reasoning intellect, however feeble it may be; and believing that the gratification and delight experienced in the contemplation of the wonders of creation here, are but a foretaste of the inexpressible felicity which, in a higher state of existence, may be our portion, I cannot but think that the minutest living atom, which the aided eye of man is able to explore, is designed for its own peculiar sphere of enjoyment, and is alike the object of His mercy and His care, as the most stupendous and exalted of His creatures.

"Le même Dieu créa la mousse et l'univers."

In nothing, perhaps, are we more mistaken, than in our estimate of the happiness enjoyed by other beings; to employ the beautiful simile of a distinguished writer*" As the moon plays upon the waves, and seems to our eyes to favour with a peculiar beam one long track amidst the waters, leaving

* Bulwer.

the rest in comparative obscurity, yet all the while she is no niggard in her lustre-for although the rays that meet not our eyes, seem to us as though they were not, yet she, with an equal and unfavouring loveliness, mirrors herself on every wave; even so, perhaps, happiness falls with the same power and brightness over the whole expanse of being, although to our limited perceptions it seems only to rest on those billows from which the rays are reflected back upon our sight." And if we admit, as all must admit who for one moment consider the marvels which astronomy has unfolded to us, that there are countless worlds around us, inhabited by intelligences, of whose nature we can form no just conception, surely, the discoveries of geology ought not to be rejected because they instruct us that ere man was called into existence, this planet was the object of the Almighty's care, and teeming with life and happiness.

Thus geology reveals to us the sublime truth— that for innumerable ages our globe was the abode of myriads of living forms of happiness, enjoying all the blessings of existence, and which at the same time were accumulating materials to render the earth, in after ages, a fit, temporary abode, for intellectual and immortal beings!

LECTURE VI.

11. The food of

1. Introductory remarks. 2. Organic and inorganic kingdoms. 3. Distinctive characters of animals and vegetables. 4. Nervous system, and sensation. 5. Diversity of animal forms. 6. Ellis's discoveries. 7. Nature of sponge. 8. Cilia, or vibratile organs. 9. The hydra, or fresh-water polype: 10. Zoophytal organization. zoophytes. 12. Mode of increase and death. 13. Corals, or skeletons of zoophytes, 14. Diversity of form and structure. 15. Geographical distribution of the polyparia. 16. The flustra, or sea-mat. 17. The vesicular corallines, or sertulariæ. 18. The gorgonia, or sea-fan. 19. The red coral. 20. The tubipora, or organ-pipe coral. 21. Madrepores. 22. The actinia, or sea-anemone. 23. Caryophyllia and turbinolia. 24. Fungia. 25. Astrea, pavonia, &c. 26. Meandrina cerebriformis, or brain-coral. 27. Appearance of the living corals. 28. Coral reefs. 29 Coral reef of Loo Choo. 30. Coral islands. 31. Fossil zoophytes. 32. Zoophytes of the chalk. 33. Zoophytes of the Shanklin sand. 34. Recent formation of chalk from corals. 35. Fossil infusoria. 36. Corals of the oolite and lias. 37. Corals of the older secondary formations. 38. Coralline marbles. 39. The crinoidea, or lily-shaped animals. 40. Encrinites and Pentacrinites. 41. Structure of the crinoidea. 42. The lily encrinite. 43. Pear encrinite of Bradford. 44. Pentacrinites, actinocrinites, and other crinoidea. 45. Derbyshire encrinital marble. 46. Geological distribution of the crinoidea. 47. Concluding remarks.

1. INTRODUCTORY REMARKS.—The secondary formations reviewed in the last discourse presented a marked increase in those extraordinary types of animal life—the polyparia, crinoidea, and other zoophytes. We observed that some deposits, as the Coral rag of the oolite, consisted almost wholly

of corals; while in the lias and other strata the mineralised skeletons of the lily-shaped radiaria were not less abundant. As we advance to the more ancient rocks, we shall find that the remains of these animals prevail in the older secondary strata, almost to the exclusion of other zoophytes; that entire mountain chains are composed of the consolidated debris of corals; and vast beds of limestone and marble, of the petrified skeletons of crinoidea. That we may understand the nature of these deposits, and be enabled to arrive at accurate conclusions as to their formation, a knowledge of the structure and habits of the existing animals is necessary; I therefore purpose devoting the present discourse to the consideration of the natural history of the recent and fossil corals, and of the lily-shaped animals.

2. ORGANIC AND INORGANIC KINGDOMS.-The beautiful world in which we are placed is every where full of objects presenting innumerable varieties of form and structure, of action and position; some of them being inanimate or inorganic, and others possessing organization or vitality. The organic kingdom of nature, in like manner, is separated into two grand divisions, the animal and vegetable. The differences between organic and inorganic bodies are numerous and manifest; but it will suffice for my present purpose to mention a few obvious and familiar characters. All the parts of an inorganic body enjoy an independent exist

ence; if I break off a crystal from this mass, the specimen does not lose any of its properties, it is still a mass of crystals as before; but if a branch be removed from a tree, or a limb from an animal, both are rendered imperfect, and the parts removed suffer decomposition, the branch withers, and the animal matter undergoes putrefaction. If crystals, which may be considered the most perfect models of inorganic substances, be formed, they will remain unchanged, unless acted upon by some external force of a chemical or mechanical nature. Within, every particle is at rest, nor do they possess the power to alter, increase, or diminish: they can augment by external additions only, and decrease but by the removal of portions of their mass.*

But

* These remarks must be taken in a general sense only, since recent experiments have demonstrated that the molecules of inorganic matter undergo modification by the slightest variation of temperature.

"Prismatic crystals of zinc are changed in a few seconds into octahedrons by the heat of the sun. We are led from the mobility of fluids to expect great changes in the relative positions of their molecules, which must be in perpetual motion even in the stillest water or calmest air; but we were not prepared to find motion to such an extent in the interior of solids. We knew that their particles were brought nearer by cold or pressure, or removed farther from one another by heat; but it could not have been anticipated that their relative positions could be so entirely changed as to alter their mode of aggregation. It follows from the low temperature at which these changes are effected, that there is probably no portion of inorganic matter that is not in a state of relative motion. Prismatic crystals of sulphate of nickel exposed to the summer heat, in a close vessel,