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tude of the universe. We are more perplexed in attempting to comprehend the organization of the minutest Infusoria,*

* Ehrenberg has ascertained that the Infusoria, which have hertofore been considered as scarcely organized, have an internal structure resembling that of the higher animals. He has discovered in them muscles, intestines, teeth, different kinds of glands, eyes, nerves, and male and female organs of reproduction. He finds that some are born alive, others produced by eggs, and some multiplied by spontaneous divisions of their bodies into two or more distinct animals. Their powers of reproduction are so great, that from one individual (Hydatina `senta) a million were produced in ten days; on the eleventh day four millions, and on the twelfth sixteen millions. The most astonishing result of his observations is, that the size of the smallest coloured spots on the body of Monas Termo, (the diameter of which is only of a line) is of a line, and that the thickness of the skin of the stomach may be calculated at from 0 to 6‰ ̄ ̄ of a line. This skin must also have vessels of a still smaller size, the dimensions of which are too minute to be ascertained. Abhandlungen der Academie der Wissenschaften zu Berlin, 1831.

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Ehrenberg has described and figured more than 500 species of these Animalcules; many of them are limited to a certain number of vegetable infusions; a few are found in almost every infusion. Many vegetables produce several species, some of which are propagated more readily than others in each particular infusion, The familiar case of the rapid appearance and propagation of animalcules in pepper water will suffice to illustrate the

rest.

In the London and Edin. Phil. Mag. Aug. 1, 1836, p. 158, there is an extract of a letter sent by M. Alexander Brongniart from Berlin to the Royal Academy of Sciences of Paris, announcing that Ehrenberg has also discovered the silicified remains of Infusoria in the stone called Tripoli (Polierschiefer of Werner,) a substance which has been supposed to be formed from sediments of fine volcanic ashes in quiet waters. These petrified Infusoria from a large proportion of the substance of this kind of stone from four different localities, on which Ehrenberg has made his observations; they were probably living in the waters, at the time when they became charged with the volcanic dust, in which the Tripoli originated. It is added in this notice that the slimy Iron ore of certain marshes is loaded with Infusoria, of the genus Gallionella.-L'Institut, No. 166.

These most curious observations throw important light on the obscure and long-disputed question of equivocal generation; the well-known fact that animalcules of definite characters appear in infusions of vegetable and animal matter, even when prepared with distilled water, receives a

than that of a whale; and one of the last conclusions at which we arrive, is a conviction that the greatest and most

probable explanation, and the case of Infusoria no longer appears to dif fer from that of other animals as to the principle on which their propagation is conducted. The chief peculiarity seems to consist in this, that their increase takes place both by the oviparous and viviparous manner of descent from parent animals, and also by division of the bodies of individuals.

The great difficulty is, to explain the manner in which the eggs or bodies of preceding individuals can find access to each particular infusion. This explanation is facilitated by the analogous cases of various fungi which start into life, without any apparent cause, wherever decaying vegetable matter is exposed to certain conditions of temperature, humidity, and medium. Fries explains the sudden production of these plants, by supposing the light and almost invisible sporules of preceding plants, of which he has counted above 10,000,000 in a single individual, to be continually floating in the air, and falling every where. The greater part of these never germinate, from not falling on a proper matrix; those which find such matrix start rapidly into life, and begin to propagate.

A similar explanation seems applicable to the case of Infusoria; the extreme minuteness of the eggs and bodies of these animalcules probably allows them to float in the air, like the invisible sporules of fungi; they may be raised from the surface of fluids by various causes of attraction, perhaps ever by ovaporation. From every pond or ditch that dries up in summer, these desiccated eggs and bodies may be raised by every gust of wind, and dissipated through the atmosphere like smoke, ready to start into life when ever they fall into any medium admitting of their suscitation; Ehrenberghas found them in fog, in rain, and snow.

If the great aerial ocean which surrounds the earth be thus charged with the rudiments of life, floating continually amidst the atoms of dust we see twinkling in a sunbeam, and ever ready to return to life as soon as they find a matrix adapted to their development, we have in these conditions of the very air we breathe a system of provisions for the almost infinite dissemination of life throughout the fluids of the present Earth; and these provisions are in harmony with the crowded condition of the waters of the ancient world, which is manifested by the multitudes of fossil microscopic remains, to which we have before alluded. (Sce Sect. viii. page 290.)

Mr. Lonsdale has recently discovered that the Chalk at Brighton, Gravesend, and near Cambridge, is crowded with microscopic shells; thousands of these may be extracted from a small lump, by scrubbing it with a nail brush in water; among these he has recognised vast numbers VOL. I.-29

important operations of nature are conducted by the agency of atoms too minute to be either perceptible by the human eye, or comprehensible by the human understanding.

We cannot better conclude this brief outline of the history of fossil Polyparies, extending as they do, from the most early transition rocks to the present seas, than in the words with which Mr. Ellis expresses the feelings excited in his own mind by his elaborate and beautiful investigations of the history of living Corallines.

"And now, should it be asked, granting all this to be true, to what end has so much labour been bestowed in the demonstration? I can only answer, that as to me these disquisitions have opened new scenes of wonder and astonishment, in contemplating how variously, how extensively, life is distributed through the universe of things, so it is possible, that the facts here related, and these instances of nature animated in a part hitherto unsuspected, may excite the like pleasing ideas in others; and, in minds more capacious and penetrating, lead to farther discoveries, farther proofs, (should such yet be wanting,) that One infinitely wise, good, all-powerful Being has made, and still upholds, the Whole of what is good and perfect; and hence we may learn, that, if creatures of so low an order in the great scale of Nature, are endued with faculties that enable them to fill up their sphere of action with such Propriety, we likewise, who are advanced so many gradations above them, owe to ourselves, and to Him who made us and all things, a constant application to acquire that degree of Rectitude and Perfection, to which we also are endued with faculties of attaining.". Ellis on Corallines, p. 103.

of the Valves of a marine Cypris (Cytherina) and sixteen species of Foraminifers.

CHAPTER XVIII.

Proofs of Design in the Structure of Fossil Vegetables.

SECTION I.

GENERAL HISTORY OF FOSSIL VEGETABLES.

THE history of Fossil Vegetables has a twofold claim upon our consideration, in relation to the object of our present inquiry. The first regards the influence exerted on the actual condition of Mankind, by the fossil carbonaceous remains of Plants, which clothed the former surface of the Earth, and has been briefly considered in a former chapter; (Chap. VII. P. 57.) the second directs our attention to the history and structure of the ancient members of the vegetable kingdom.

It appears that nearly at the same points in the progress of stratification, where the most striking changes take place in the remains of Animal life, there are found also concurrent changes in the character of fossil Vegetables.

A large and new field of investigation is thus laid open to our inquiry, wherein we may compare the laws which regulated the varying systems of vegetation, on the earlier surfaces of our earth, with those which actually prevail. Should it result from this inquiry, that the families which make up our fossil Flora were formed on principles, either identical with those that regulate the development of existing plants, or so closely allied to them, as to form connected parts of one and the same great system of laws, for the universal regulation of organic life, we shall add another link to the chain of arguments which we extract from the interior of the Earth, in proof of the Unity of the Intelli

gence and of the Power, which have presided over the e tire construction of the material world.

We have seen that the first remains of Animal life yet n ticed are marine, and as the existence of any kind of anima implies the prior, or at least the contemporaneous existen of Vegetables, to afford them sustenance, the presence sea weeds in strata coeval with these most ancient anima and their continuance onwards throughout all formations marine origin, is a matter of a priori probability, which h been confirmed by the results of actual observation. Adolphe Brongniart, in his admirable History of Fossil Veg tables, has shown, that the existing submarine vegetati seems to admit of three great divisions which characterize, a certain degree, the Plants of the frigid, temperate, a torrid zones; and that an analogous distribution of the fos submerged Algæ appears to have placed in the lowest a most ancient formations, genera allied to those which no grow in regions of the greatest heat, whilst the forms of m rine vegetation that succeed each other in the Seconda and Tertiary periods, seem to approximate nearer to tho of our present climate, as they are respectively enclosed strata of more recent formation.†

• Histoire des Végétaux Fossiles, 4to. Paris, 1828.

† See Ad. Brongniart's Hist. de Vég. Foss. 1 Liv. p. 47.-Dr. Har in the Journal of the Academy of Nat. Sc. of Philadelphia, 1831, a Mr. R. C. Taylor in Loudon's Mag. Nat. Hist. Jan. 1834, have publish accounts of numerous deposites of fucoids, as occurring in repeated t layers among the Transition strata of N. America, and extending ove long track on the E. flank of the Alleghany chain. The most abund of these is the Fucoides Alleghaniensis of Dr. Harlan. Mr. R. C. Tay has found extensive deposites of fossil Fuci in the Granwacke of cen Pennsylvania; in one place seven courses of Plants are laid bare in thickness of four feet, in another, one hundred courses within a thi ness of twenty feet. (Jameson's Journal, July, 1835, p. 185.) I h also seen Fucoids in great abundance in the Grauwacke-slate of Maritime Alps, in many parts of the new road between Nice and Gen I once found small Fucoids dispersed abundantly through shale of Lias formation, from a well at Cheltenham. The Fucoides granula

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