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NATURAL HISTORY, as commonly understood, refers to the study of animals and plants. A profound truth is contained in this popular acceptation of the term. For in order that either animals or plants may be thoroughly understood, both require to be studied; while the two together constitute a group of natural objects which may be considered apart from the non-living world. Animals and plants taken together, then, form the subject-matter of a distinct science, BIOLOGY-the science of living bodies.

The study of the Natural History of living creatures has of late assumed a greater importance than it was ever before thought to possess. Recent advances in science seem also to indicate that this history needs re-writing from the standpoint which our most expert and zealous biological explorers have succeeded in attaining. No scientific NEW SERIES.-VOL. XXX., No. 1

questions have perhaps excited greater interest than those which concern the problems of animal or vegetable life, the origin of such life, and the origin of its multitudinous forms.

Apart, however, from such interest in it as may be due to controversies of the day, the love of this study is one which must grow upon men as they advance in the knowledge of their own organisation, owing to the very conditions of their existence. For man is so related to other living creatures, that fully to understand himself, he must, more or less thoroughly, understand them also.

Every increase in the knowledge of the organic world has its effect upon the study of man, and helps him not only towards a better knowledge of his own organisation, but also helps in the pursuit of his own happiness and in the fulfilment of his duty.

To man alone is at the same time ap

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portioned the physical enjoyment, the intellectual apprehension, and the asthetic appreciation of that marvellous material creation which on all sides sur rounds him, which impresses him by its many active powers, and of which he alone forms the self-conscious and reflective portion.

His connection with it is, indeed, most intimate, partaking as he does all the orders of existence revealed to him by his senses-inorganic or organic, vegetative or animal. The mineral matters of the earth's solid crust, the chemical constituents of oceans and rivers, even the ultimate materials of remote sidereal clusters, contribute to form the substance of his body. The various activities of the vegetable world have their counterpart in the actions of that body. When we study the laws of growth, as in the creeping lichen or gigantic eucalyptus, or the actions of roots or leaves, when we follow the course of the spore dropped from a fern frond, or when we investigate the meaning and action of flowers of whatever kind, we come upon processes which the human body is also destined to perform. But the animal world especially concerns man, since, being an animal himself, he shares the pleasures, pains, appetites, desires, and emotions of the sentient myriads which people earth, air, and water. His frame, like theirs, thrills responsively to the ceaseless throbbings of that plexus of ever-active agencies, lifeless as well as living, which we call the Cosmos. Thus man plainly shares in the most diverse powers and faculties of his material fellow-creatures, and he sees also reflected by such creatures, in varying degrees, those different kinds of existence which unite in him. Man sees this reflection, and in so seeing recognises as existing in himself a faculty much above every power possessed by any other organism. Unlike even the highest of the brutes, he not only feels the Cosmos, but he thinks it. He is not only involved with it in an infinity of relations, but he recognises and reflects upon many of such relations, their nature and their reciprocal bearings. "The proper study of mankind is man ;" but to follow out that study completely we must have a certain knowledge of the various orders of creatures in the natures of which man,

in different degrees, participates. Man's intellect is indeed supreme, nevertheless it cannot be called into activity unless first evoked by sense impressions which he shares with lowly animals; nor can his intellect, even after it has been aroused into activity, continue to act save by the constant renewal of sense impressions-real or imagined. Such impressions give rise, in him, to imaginations, reminiscences, anticipations, and emotions, which serve as materials for the exercise of intellect and will; and as these imaginations, reminiscences, anticipations, and emotions are possessed also by brutes, it is to the study of such creatures that we must have recourse to obtain one of the keys needed to unlock the mystery of man's existence.

In addition to the above considerations, the organic world is of course useful to us in a variety of ways. Man, as lord over all other organisms which people the globe, rightfully disposes of them for his profit or pleasure, finding in the investigation of their various natures an inexhaustible field for his intellectual activity, and in their forms and relations a stimulus for his deep-seated apprehension of beauty. Thus, many considerations and influences concur to impel us to the study of Nature, and especially the Natural History of the many living creatures which are so variously related to us.

But a Natural History which shall include both animals and plants must be a history of creatures of kinds so various that their number baffles the power of the imagination, as a little reflection will suffice to show. Beasts alone are numerous, but very much more so is the group of reptiles. Serpents and lizards, indeed, so swarm in the hottest regions of the globe that, in spite of the multitude of forms already described, it is not impossible that nearly as many more remain to be discovered. More than ten thousand different kinds of birds have been now made known to us, and fishes are probably not less numerous than all the other above-mentioned animals taken together.*

*The number of kinds of fishes described

by ichthyologists only about equals the number of birds. But then ornithologists reckon such small differences as making a distinction of kind, that if ichthyologists pursued a similar

Beasts, birds, reptiles and fishes, however, considered as forming one group, constitute but a comparatively small section of the world of animals. Creatures allied to the snail and oyster, but all of different kinds, exist in multitudes which are known to us, but doubtless also in multitudes as yet unknown. Worms form a division so varied in nature and so prodigious in number, that the correct appreciation of their relations one to another and to other animals-their classification-forms one of the most difficult of zoological problems. Coral-forming animals and cognate forms, together with star-fishes and their allies, come before as two other hosts; and there are yet other hosts of other kinds to which it is needless here to refer. Yet the whole mass of animals to which reference has yet been made is exceeded (as to the number of distinct kinds) by the single group of insects. Every land-plant has more than one species of insect which lives upon it, and the same may probably be said of at least every higher animal-and this in addition to other parasites which are not insects. The lowest animals have not yet been referred to, but the number of their undiscovered kinds which may exist in the ocean, and in tropical lakes and rivers, may be suspected from the variety we may obtain here, in a single drop of stagnant water. Recent researches, moreover, have shown us that the depths of the ocean, instead of being (as was supposed) lifeless as well as still and dark abysses, really teem with animal life. From those profound recesses also creatures have been dragged to light, forms which were supposed to have long passed away and become extinct. And this leads us to yet another consideration. It is impossible to have a complete knowledge of existing animals with out being acquainted with so much of the nature of their now extinct predecessors as can be gathered from the relics they have left behind. Such relics may be bones or shells imbedded in muddy deposits of ages bygone, and which deposits have now turned to rock, or may

course the number of fishes reckoned as distinct would be much in excess. Besides, there are probably many more new kinds of fishes to discover than there are of birds.

consist of but the impress of their bodies, or only a few footprints. Rich as is the animal population of the world to-day, it represents only a remnant of the life that has been; and small as our knowledge may ever be of that ancient life (from imperfections in the rocky record), yet every year that knowledge is increased. What increase may we not also expect hereafter, when all remote and tropical regions have been explored with the care and patience already bestowed on the deposits which lie in the vicinity of civilised populations?

But, besides the forms of animal life which are thus multitudinous, acquaintance must also be made with myriads of vegetable forms in order to understand the Natural History of animals and plants. Numerous 'as are the different kinds of trees, shrubs, creepers, other flowering plants, ferns, and mosses peculiar to each great region of the earth's surface, the total number of the lowest flowerless forms is yet greater. Known sea-weeds of large or moderate size are numerous, but some naturalists think there are still more yet unknown. But, however that may be, their number is small compared with the swarms of minute algæ and fungi which are to be found in situations the most various. For not only do fungi live upon the surface of other plants, but they penetrate within them, and, as " mould," deprive the stoutest timber of its substance and resisting power; they devastate fields of promising grain, destroy the hope of the vine-grower, and ruin our homely garden produce. And as certain animals are destined to nourish themselves on certain plants, so do different kinds of these lowly plants nourish themselves on different animals. Ulcers and sores may support their appropriate vegetation, the growth of which has caused havoc in many an hospital ward, with an atmosphere teeming (as it often teems) with their minute reproductive particles. Analogous particles of other plants even form no insignificant part of our coalfields, as the produce of coral animals has built up large tracts of land in the State of Florida and elsewhere, and as a vast the Atlantic from the ceaseless rain of deposit is accumulating on the floor of dead microscopic shells which have lived in its surface waters.

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