perform the nutritive functions of their life, plants absorb, breathe, assimilate, perspire, and excrete. Nor is this allthey sleep by night, awake by day, and are of different sexes. "Let us, in imagination, peer into the ultimate particles of the living, active, moving matter, and consider what we should probably discover. Were it possible to see things so very small, I think we should discover spherules of extreme minuteness, each being composed of still smaller spherules, and these spherules infinitely minute. Such spherules would have upon their surface a small quantity of matter differing in properties from that in the interior, but so soft and different that the particles might come into very close proximity. In each little spherule the matter would be in active movement, and new minute spherules would be springing into being in its central part. Those spherules already formed would be making their way outwards so as to give place to new ones which continually rise in the centre of every one of those animated particles. . . . The change which occurs in the living centre is probably sudden and abrupt. The life flashes, as it were, into the inanimate particles and they live."1 This is a scientific conception of the manner in which the work was done, when God said "Let the earth bring forth grass." It is really a very nice question whether we can trace any difference between the ultimate plant and the ultimate animal. Corals, long taken for vegetables, are, after all, animals. There are certain minute fresh-water animals which may be cut to pieces and multiplied exactly as plants are multiplied by cuttings. Cuvier, in the first volume of his great work, "Regime Animal," says, an animal has power of locomotion, an internal reservoir in which to carry its food, a digestive cavity, and an alimentary canal. He further states, that an animal must possess muscles, nerves, and all that apparatus, by which locomotion is brought about; must have a more complicated structure than a plant-for while a plant is composed of oxygen, hydrogen, and carbon, an animal possesses also nitrogen. He claimed, as an essential feature 1 Dr Beale's Prot., 3d ed. p. 277. in animals, that they took in oxygen, and gave out carbonic acid; while plants took in carbonic acid, and gave out oxygen. Now, as matter of fact, very few of these diagnostic marks stood the test of further inquiry. There are innumerable lower organisms which feed as animals, but have no permanent digestive cavity. They are soft masses which take in food at any point of their circumference, and get rid of it in the same way. As to an animal being of a more complicated structure, we find, by means of the high powered microscope, that animal and plant start from one common point; all the diverse tissues issuing from a fundamental form the cell: the wood cell of a plant being developed in the same way as a scale of the epidermis in man. The starting point, both in plant and man, is a mass of similar nucleated cells. As to chemical composition, recent investigations show that all living matter contains nitrogen. As to the statement that animals take in oxygen, and give out carbonic acid; while plants take in carbonic acid, und give out oxygen; it is now shown that, when the sun ceases to shine, the plant exhales carbonic acid just the same as an animal; and that colourless plants and fungi exist like animals-taking in oxygen and giving off carbonic acid. The mobility of plants also is now well established. Multitudes of plants are all their life in active motion; and no clear line can be drawn between the contractility of plants and animals. Considering the insectivorous plants, it is almost impossible to distinguish by any visible character, a difference in the reflex action existing in plants and that existing in animals: so that no one can say whether plants have or have not a nervous system. It is true, however, a plant is able to make its bodily substance out of inorganic chemical substances; which an animal cannot do. A bean will grow in a nitrate of ammonia and saline solution; and the resulting substance of the bean contains matters of which there is no trace in the solution. An animal can only break down and appropriate the protein compounds furnished by other animals or plants. "He is the aristocrat, and the plant is the ideal prolétaire of the living world." The Bacteria, generated in vegetable and animal infusions by means of germs which float in the air, are Classification of Plants. 187 vegetable; but that other busy little body generated in the same infusion, which Professor Huxley calls "Heteromita Lens," may be animal; there is a border territory between the two kingdoms, a sort of neutral land, the inhabitants of which cannot be separated with any certainty, or brought to their proper allegiance in either kingdom. We cannot as yet say, "Here the line between the animal and the plant must be drawn." Tournefort's system of vegetation contains twenty-two classes; that of Linnæus, twenty-four; the natural method by Jussieu, the basis of a complete scientific tabulation, comprises fifteen classes, one hundred natural orders, and about one thousand seven hundred and forty genera. The sequence of orders now generally adopted is that proposed by De Candole. The result of all the various schemes establishes two primary divisions of all plants :— a. Phænogams, or Flowering Plants. I. Dicotyledons-plants with two seed lobes; b. The Cryptogams subdivide into— 3. Acrogens-vascular plants for the most part; "Beyond this, except in the case of Cryptogams, it is difficult to establish any subdivisions higher than that of Orders; and of the Phænogamous Orders themselves, it is astonishing how few are absolutely limited." 2 To assert that Moses has given, in his brief account of the formation of plants, a prophecy of scientific classification would be unwarrantable; but it is, to say the least, remarkable that his "Grass," "Herb," "Plant" (Gen. ii. 5), "Tree," should happen to be that number of which scientific men say "It is difficult to establish any divisions higher than that of orders;" "In the popular mind, plants are still classed under the heads of trees, shrubs, and herbs; and this serial classing, according to the simple attribute of magnitude, 1 "Descriptive and Analytical Botany :" arranged by Dr Hooker, p. 165. "Descriptive and Analytical Botany :" arranged by Dr Hooker, p. 991. 2 swayed the earliest observers." The utter indefiniteness of ancient sacred description, wanting even the rudiments of scientific form, may fairly and safely be taken as a commendation: for as to Phænogams, the first and chiefest of the Botanical Kingdom, "a large proportion either are connected with one or more others by a series of interminable genera, or contain genera which present so many of the characters of other orders, that it is altogether uncertain in which of them they shall be placed." Nor is it to be forgotten, that the roots of the Hebrew words themselves yield a more correct and scientific meaning, if such be required; but it is more akin to the spirit of the Divine narrative to take the Scriptural simple and popular compendium-grass, herb, plant, tree-which men generally look upon as including all vegetation. Had Moses endeavoured to give us some idea of the results of evolution, so far as they are now accurately known, he could not better have described them than "by seizing the successive salient points in a continuous history of myriads of years-projecting them on the mind like a succession of dissolving views, which gather into distinctness or fade away into nothingness, like the dawning and the parting of the day." No hard and fast lines can be drawn. We have remarked already that of the two hundred and seventy-eight of the Phænogamous or flowering orders, described by Dr Hooker, "Descriptive and Analytical Botany," excluding those containing only one or two genera, it is astonishing how few are absolutely limited. With flowerless plants, or Cryptogams, the case is different; but even these can only be strictly limited, if it be limitation, by making them very comprehensive. The same fact extends through all natural history. There are whole classes of organisms to which it is impossible, even with the widest reservations, to apply the old idea of species, with its immutability of essential characteristics.1 Botanical and other 1 "Principles of Biology," vol. i. p. 295: Herbert Spencer. * "Descriptive and Analytical Botany :" arranged by Dr Hooker. 3 Rev. T. G. Bonney, University Sermon:" Cambridge, April 29, 1877. "The Doctrine of Descent:" Professor Oscar Schmidt. Order of Introduction. 189 systems are of a superficial description; they rest upon forms which are in an extreme grade of mutability; and it is not a little wonderful that Scripture should give a general formula which substantially contains the present scientific classification. It may be said of the creative narrative-" only those vegetable productions are meant which are useful to man; and that trees and plants of this character, were of latter appearance on earth, and only just preceded man. The best reply to such an objection is utter denial. One must not be tempted into argument that the families of vegetables and animals were probably introduced according to the order in which naturalists have of late classed the flora and fauna. It is better to rely on the general and comprehensive character of Scripture; it were needless to seek scientific and technical accuracy; for, really, the objection confirms the ancient narrative. Grass, herb, tree, fruit-tree are simple comprehensive words, which of old, and even now, popularly sum up all vegetable life. Vegetation grew from the simpler to more complex forms. The earliest plants which are known in the fossil condition to geologists are fucoids, and they were probably true sea-weeds or algæ. In fossil shells of the Palæozoic Age, traces of the presence of microscopic fungi, such as Achlya Penetrans (Duncan), have been found. Some of the higher cryptogams, closely allied in their construction to those now existing, have been got out in the fossil condition from the Devonian and Carboniferous strata, associated with Calamites and Lepidodendron. Thus the earliest plants were marine. Then came land forms of simple and more complex construction, but still belonging to the lower orders. Conifers, or gymnospermous exogens, were with these and other plants in the Carboniferous age; and thus there was structural variety in those remote days. Flowerless plants, lacking both stems and leaves, were succeeded by those possessing stems and leaves. The early plants could contribute little, if at all, to the support of high animal life; nevertheless, grass and herb are of ancient origin, existed very early; their existence may certainly be inferred, from the presence of various insects in the Lias and Tertiaries. Dicotyledons, of angio |