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contains many admirable criticisms, and some allusions to the discoveries which will give the author posthumous fame. There are passages of great beauty in thought and expression, and many suggestions of moment; nor are these anonymous productions wanting in that spirit of truthfulness, kindness, affection, and playfulness, which distinguished Edward Forbes as a companion and teacher. We can find nothing to offend, and there is much to please and instruct ; yet while we recommend the book as one which may be useful to the young in forming the taste, and in cultivating a love of natural science, we are bound to say that it does not place this distinguished man, admirable in literature and in science, in that position which his genius demands, and his friends anticipate. From its pages, however, we may collect his opinions upon many subjects connected with the sciences he studied, and draw from them many inducements to the adoption of similar pursuits.

It has been sometimes said, and ignorant people pretend to believe it, that intellectual improvement of a high order makes a man retiring and unsocial. Our author answers that charge :

"There is no greater or more prevalent mistake than the supposition that the intellectual development is inconsistent with a keen sense of enjoyment. There are, it is true, a considerable number of grave, dull, would be sages, moving at a snail's pace, with a snail's gravity, through society-looking, as Oken says in his transcendental philosophy, like so many prophesying goddesses seated on tripods. But nine out of ten of them maintain a philosophic fame only on the credit of an ominous and unbroken silence; the tenth on the strength of supporting some incomprehensible paradox, which neither he nor the stupid people who listen to him comprehend. Your real philosopher is neither uncommunicative nor dogmatic; he utters his words of wisdom at the right time and place, but on ordinary occasions is like other men, and enjoys himself, perhaps even more intensely, when enjoyment is afloat. Davy was one of these, as every man of genius is, and has been. Hence the unaffected enthusiasm with which Sir Humphrey plunged into stream and pool, and pursued his salmon fishing hobby all over Europe. And whilst the zest for pleasure humanizes the philosopher, his science and taste in turn elevates his pleasures. The objects of his sport become to him a source of interest, such as they cannot be to common men. In their forms he delights to trace all-wise contrivance, and in their instincts the guidance of superhuman wisdom. He follows them to their haunts, marking every charm of the landscape on his way, and every turn and varying chance of his sport suggests reflections on men and things-fanciful analogies, it may be, but not the less true-such as give eloquence to his tale of adventure, and render the records of his amusements as classical as these · Conversations of Fly Fishing' by Davy.'-pp. 291, 292.

The following passage is a good example of the pleasing manner the progress of time; they deny the assertion, and thus reduce the Vestigian to the disreputable position of being called on to prove his assertions.

"The speculator in development,' says Professor Forbes, 'was not content to misinterpret, he misrepresented (probably unconsciously) the facts upon which he founded his theory, or knew them so imperfectly as to forget to mention the most important. Professor Sedgwick's searching examination of such mis-statements cannot fail to expose the fallacies of the work he reviews, and must do good service, especially among students, by preventing their reception of mistakes for facts. This is conspicuously the case with that part of the inquiry which deals with the first appearance of organized beings. If the theory of progressive development in the Lamarckian sense be good for anything, the earliest creatures of which we find traces should be the simplest and lowest forms, not only of their tribes but of all creatures. To the practical geologist it is needless to say that such is not the case; but so positively and frequently has the statement to the contrary been put forward, that strong and repeated denials, and an appeal to facts over and over again, are necessary to convince numerous able men, many of them men of science, who are not practically conversant with geological researches. Yet no fact is more certain than that the remains of the oldest animals yet discovered do not belong to the most rudimentary forms.

Instead of Sponges, hydroid Zoophytes, Bryozoa, and Formanifera, the simplest types which, under the conditions indicated by the strata, could be expected to occur in the most ancient Palæozoic deposits, we find asteroid and helianthoid Zoophytes, Cephalopods (the highest of Mollusca), Brachiopods, and Trilobites. No person, whose acquaintance with zoology is sufficient to enable him to estimate the position in the animal series of a Cuttle-fish or a Crustacean, can for a moment hold the notion that the Palæozoic fauna was rudimentary, if he possesses any familiarity with the fossils of the Silurian system. Every day we are learning more and more to recognise the common-sense view, that the appearance of genera and species in time has been, from the beginning to the present, determined simply by the physical conditions adapted to them. The Creator, willing that there should be no great epoch of desolation, has called into being species after species, organizing each for the circumstances amidst which it was destined to live.'-pp. 14-16.

An hypothesis which assumes that every variety of organization has its origin in one that is a grade lower, and after its appeals to geology for the support of its assertion is found by the very evidence given under its subpæna to be false, can have no favour from honest minds. It is a vain, half-witted, foolish imagination; or, still worse, a sham and imposture. It assumes that the forms of life are progressive, and it lacks a beginning. Where it desires to find rudimentary forms, rocks yield the relics of an organization of a high character. Nor is this all. To prove its claim upon our credence it should show an uninterrupted propunishment of a man who, in his enthusiasm for science, braves the extremes of temperature, lives in forests inhabited by beasts of prey and venemous snakes, and visits the most uncivilized of human kind to observe their habits, learn their traditions, and investigate the geology or natural history of the country they occupy, without a thought of gaining money, or a single commercial idea in his mind. Mr. Fortune would have needed no apologist had he failed in his attempt when he entered the interior of China, by the desire of the East India Company, to study the manufacture of tea, and obtain plants—of which he fortunately secured twenty thousand—to be sent for cultivation on the slopes of Himalaya. But who would have undertaken his defence if his commercial enterprise had failed, by a discovery of his incognito, from his enthusiastic ardour to get a nearer view of a new cypress, and obtain a few seeds for the nurserymen in Europe? And yet such might have been the result if a second thought had not suggested that to scale an innkeeper's wall for such a purpose would be an indecorous proceeding for a Chinaman.

The hypothesis of the development of organization in succession of time, so speciously stated upon assumptions falsely called geological facts, by the author of the Vestiges of Creation,' was vigorously opposed by Professor Forbes in that kindly spirit which aims at the correction of an error rather than the award of punishment for a fault. It is an hypothesis unsustained by a single fact in paleontology, and rests entirely upon an imaginary progression of organization in the succession of fossil-bearing rocks. The subject is now almost worn out, but there may be some curiosity to know what so eminent a naturalist said respecting it. The assumption upon which the hypothesis is built is thus stated by the author of the · Vestiges,' who is supposed to be Mr. Robert Chambers, of Edinburgh :

'It is clear, and can now be asserted on the authority of the first naturalists of the age, that in all the conspicuous orders of animals, there have been in the progress of time strong appearances of a progress of forms from the more simple to the more complex, from the more general to the more special, the highest and most typical forms being always attained last. It cannot be pretended in all cases that we have an unbroken and perfect series, exhibiting these gradations, for the stone book is one wanting many leaves ; but in the orders that have been best preserved there is such a well-marked succession leading on from one degree of organization to another, that the general fact of a progress in all the orders is not to be doubted.' — Vestiges,' p. 140.

Now 'the first naturalists of the age' do not admit that there has been an increasing perfection of organization as the result of

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the conviction that all species of animals descended from single created progenitors. Admitting this, which to us appears an indispensable conjecture in science, and a fact in revelation, each species, wherever we may now find the individuals, must have been diffused from a specific centre; or, in other words, there must have been some geographical point in which the primogenitors were created, and to which all their offspring may be traced. The work of the naturalist in determining these specific centres is similar to that of the ethnologist, when he attempts to tread back the road a race of mankind have traversed to the locality in which their early ancestors dwelt, and from which a portion of their tribe wandered. That this view of the distribution of life in its specific forms is correct admits of no reasonable doubt; for if a fact can be perfectly explained by a single cause, it is evidently false to assume, as a primordial condition, a multiplication of that cause.

Upon this assumption Professor Forbes, as palæontologist to the geological survey, founded those inquiries, the results of which he has stated in his admirable paper ‘On the Connexion between the Distribution of the Existing Fauna and Flora of the British Isles, and the Geological Changes which have affected their area, especially during the epoch of the Northern Drift.'

Before any connexion can be traced between geological changes and the introduction into Britain of the existing plants and animals, we must ascertain by what means such an isolated area may have been furnished with its present fauna and flora. There are three modes in which it may have been done, either wholly or in part—by creation within the area, transport to it, or migration before isolation. In one or more of these ways the British Isles must have received the species of animals and plants which now exist on their surface. That it was not by special creation within the area, to any large extent, is probable from the fact that the terrestrial animals and flowering plants, with few exceptions, are identical with continental species. That it was by transport is improbable, for although the great mass of cryptogamic plants, a few phanerogamia, and a few terrestrial animals, may have found their way across the separating waters by the agency of currents; or, in the case of the plants, their seeds may have been conveyed by the winds or birds through the air; yet, after making full allowances for all likely means of transport at present in action, there remains a residue of animals and plants which we cannot suppose to have been transported, since either their bodily characters, or certain phenomena presented by their present distribution, prevent our entertaining such an idea.'

Rejecting then the two former possible modes, one as improbable, and the other as insufficient, the British Isles must have been colonized by the animals and plants now existing on their surface advancing from other lands previous to the isolation of our island homes. To determine at what periods these migrations occurred opens a wide field of investigation, for it is not only necessary to ascertain in what other countries our plants and animals are found, but to fix by incontrovertible geological evidence the time when the British Isles were separated from the continent of Europe. These are questions with which Professor Forbes fairly grapples, and, as we think, fairly selves. No better evidence of his genius and profound knowledge of his science, and the great loss we have had in losing him, can be given than in an abstract of his research and reasoning upon this subject. But as we are compelled by the limitation of pages to confine our remarks the first part of the essay, we recommend the memoir itself to the study of the reader, as a process of inductive thought, to which the geologist may refer as an answer to every taunt which charges him with the folly of guessing at conclusions, and being governed by his imagination.

The majority of British plants, those which are widely distributed, and, par excellence, form the_flora of the country, are also found in Central and Western Europe, and are by Forbes designated Germanic. 'Every plant universally distributed in these islands is Germanic; every quadruped common in England, and not ranging to Ireland or Scotland. The great mass of our pulmoniferous mollusca have also come from the same quarter.'

There are, however, certain local floras which may be divided into four classes :-1. A small number of plants found in mountainous districts on the west and south-west of Ireland, natives of the north of Spain; 2. A flora found in the south-west of England, and south-east of Ireland, identified, in relation at least, with that of the Channel Islands, and the neighbouring provinces of France ; 3. The chalk plants; so called from their being found on the cretaceous rocks of the south-eastern part of England and on the opposite coast of France on the same geological formation ; 4. The Alpine or mountain flora. To study the plants of this last division we must visit the loftiest peaks in Scotland. The mountains of Cumberland and Wales do not support many of the species which are found in the Highlands ; but with one exception (Lloydia scrotina) all that can be found in other lofty districts of the British Isles are native there. And it is also worthy of remark, that while Scotland owns many Alpine species which do not grow on ridges of more southern latitude, the Scandinavian Alps support all the mountain plants of the Highlands, with many peculiarly their own.

According to the hypothesis which has been assumed, all

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