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generation, and that the earth is reduced to ordi

nary propagation.

Jamque adeo fracta est ætas, ecfœtaque tellus
Vix animalia parva creat, quæ cuncta creavit
Sæcla, deditque ferarum ingentia corpora partu.

The germs of life he supposes to be everywhere provided through the universe-in air, food, waterready to be developed into species by the warmth of the sun, in water or mud disposed to fecundity, so that all life has proceeded from the sea. Whether this constitution of things be ascribed to laws of nature or the design of the Creator, he regards with indifference, being satisfied that such a condition of things is real.

The difficulty of the change from watery life to aërial life, he regards lightly.

'A hundred millions of individuals must have perished, without being able to assume the new habit of life, but it is enough if two have survived the trial, to give permanence to the race.' Here is one example of the process:

'It may have happened, as indeed we know it often does happen, that flying-fishes fell into brambles or pastures, from which it was impossible to return to the sea by the effort which brought them from it, and that in this state they acquired a greater power of flight. Their large fins, no longer bathed by the waters of the sea, divided and opened in drying; the separated fin-rays prolonged themselves, and became covered with barbs, or to speak exactly, the membranes which had previously held them together were metamorphosed. The barb formed of these separated pellicles, lengthened itself; the skin gradually covered itself with a down of the same colour, and this down increased. The subventral fins, which, as well as the large fins, assisted their promenade in the sea, became feet, and served them for walking on the earth. Some other small changes took place in their shape. The beak and neck of some were lengthened, of others shortened; and so of the other parts of the body. But still the conformity of the original figure remains on the whole; and it is and always will be easy to recognize.'

So much for the origin of Birds! By processes equally easy and satisfactory, the sea is shewn to be the parent of quadrupeds and men.

GERMS OF LIFE.

Buffon adopted similar views as to the derivation of the forms of life, and was followed by one greatly superior in real knowledge of nature, who has given to the dreams of De Maillet a regular form and delusive symmetry1.

Lamarck supposes all the phenomena of life may be accounted for upon electro-chemical principles, and that the higher and more intelligent races of animals may have been gradually formed by the plastic power of nature, out of the smallest and simplest. By nature, we are to understand a certain order of causes and effects, constituted by the will of the Supreme Author of all things, and appointed to produce all the phenomena of the material world. In obedience to this secondary power he supposes that the attractive force of matter is sufficient to produce small portions of gelatinous substance, capable of being acted on by these powerful agents, caloric and electricity, and that when thus acted on they exhibit vital energies; in other words, that caloric and electricity acting on appropriate dead matter may convert it into living organic matter. Further, that the modifying influence of circumstances has caused these indefinite organic living masses to be extended into various animal forms; that first were produced the more simple, from these, by methods of reproduction, aided by the continued action of the same vital fluids and under the influence of changed circumstances and acquired habits and desires, other different and superior races of animals may have been formed. In this hypothesis we have three assumptions: First, that some of the inferior tribes of plants and animals are producible by the agency of caloric and electricity from dead matter, and that locomotion in some of these is accomplished by the external influence of these exciting fluids, and not by the inherent power of the creature.

1 Philosophie Zoologique and Introduction to Animaux sans Vertèbres.

Secondly, that the organic beings thus originating are capable of indefinite change of form and structure from the force of external circumstances.

Thirdly, that new habits of life are acquired with the new structures; that individual desires or longings have influence in the further development; and that the acquisition and exercise of the senses, instinct, reason, hope and fear, memory of the past, and expectation of the future, is a part of this stupendous chain of metamorphism with a tendency to progressive improvement.

Neither of these assumptions is proved, or rendered probable; but rather becomes less and less acceptable the more we consider the illustrations suggested by the author, which are scarcely less surprising than the instance already quoted from Telli

amed.

The foundation in truth for this hypothesis is the unquestionable power of adaptation which living creatures possess, through exercise of the organs of life, by which some change is possible in structure and some change in function also, the new qualities being in some degree transmitted to the descendants.

There is no need to mention in detail the views of other and later continental writers, for none have been more ingenious, more plausible, or more explicit; nor has the proof which is wanting to sustain the propositions of Lamarck been supplied by his followers in any country.

The speculations of Lamarck have met with a full and fair examination in Lyell's Principles of Geology, leading to a deliberate rejection of the hypothesis, and a decisive affirmation of the reality of species in nature. The following is his recapitulation of the result of the inquiry.

'For the reasons therefore detailed in this and the two preceding chapters, we may draw the following inferences in regard to the reality of species in nature:

'1. That there is a capacity in all species to accommodate themselves, to a certain extent, to a change of external circumstances, this extent varying greatly, according to the species.

'2. When the change of situation which they can endure is great, it is usually attended by some mo

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