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in this particular was effected, and that the transformed or transforming animal acquired, ready made, this new centre of its circulation suited for its new position in life. There could be no formation by gradual mutation of ages in this point. The reptile must have its peculiar heart, and so must the bird. “Slight modifications' are not admissible here. Life depends every minute on the action of the heart, there can be no empirical experiments here, po ‘slightly plastic' attempts at a new machine; to suppose an animal living with an intermediate heart for a million of years, must be too desperate a venture for the most ardent admirers of Natural Selection. That dextrous metaphor may be always on the watch to take advantage of the slightest beneficial change,' but it would soon be discovered that no change at all could be made, without destroying life, and utterly ruining the attempt at metamorphosis.
Therefore we say that a transition from a reptile with a tripartite heart to a bird with its heart of four cavities is impossible ; supposing we were to concede that the various genera and species of birds have slided into one another, that a blackbird may have had a common ancestor with a crow, and a goose have issued from a swan. This is not the question of the mutability of species, already discussed, but of a much wider separation, nature's grand organic distinctions in which, by a few settled arrangements of internal organism, certain animals are totally separated from one another in the scheme of life; but which, nevertheless, Natural Selection is supposed to have surmounted by those who adopt the theory of Transmutation.
The distinction of the structure of the heart, an efficient rule for dissociation and sejunction, answers well for a negative purpose; but for classification something more
precise is needed, and this has been effected by Cuvier, who looked more to the nervous system for an accurate distribution of the animal kingdom. Guided by this indicator he established his four divisions of Vertebrata, Mollusca, Articulata, and Radiata, and though these divisions, with the exception of the first, are named from their external appearance, the three first are defined by characters exclusively drawn from the internal organization. The nervous system is, in fact, “the essence and prime distinction of the animal' (Owen); its mind, so to speak, depends on this ; its peculiar character, the result of its sensibilities, is derived from the nervous centre and its ramifications; its body is constructed to suit the impulse of its will, and its will by the nervous system rules and directs the body.
The vertebrata rise in the comparative scale of existence through the peculiar arrangement of their nervous provision; Mollusca (oysters, &c., &c.) are obviously creatures of a lower life than the vertebrated fishes. In the Mollusca* the centres of the nervous system are sometimes disposed irregularly through the general cavity of the body, sometimes aggregated round the gullet, sometimes arranged with more symmetry along the abdomen, yet seldom better cared for or protected than the neighbouring viscera.
This provision, inferior and imperfect as it appears, compared with the nervous furniture of the vertebrata, is fully adequate for the wants and habits of those lower animals ; many of which can neither see nor hear, and have but little need of locomotion in the search for their food.
The nervous centres of the Mollusca consist of several detached masses placed in different parts of the body, without regularity of distribution or symmetrical arrangernent.'—Jones, 4.
When therefore life was to be exalted into a more vigorous manifestation, the vertebral column was formed, a case and protection for the nervous system, which as the spinal marrow, that mysterious albuminous electric pulp'(Owen). is there aggregated in force, and communicates with the citadel, the brain, shielded in another cavity, the skull.
Two strongly-built cavities, the vertebral column and the skull, protecting the nervous system, characterize the vertebrated* class; and this is wanting in all the inferior invertebrated animals. This is one of those great organic distinctions which bar a translocation of life from one class to another; any pretended transmutation here would be simply fabulous, as much as to pretend that a rock was changed into a tree.
“There can be no doubt,' says Professor Rymer Jones, that the nervous system must be regarded as the very essence of being of all creatures, with which their sensations, volitions, and capability of action are inseparably connected ; and such being the case it is a legitimate inference, that the capacities and powers of the several tribes are in im. mediate relation with the development and perfection of this supreme part of organization, and their entire structure must be in accordance with that of the nervous apparatus which they possess. The nature of the limbs and the external members, the existence or non-existence of certain senses, the capability of locomotion, and the means of procuring food, must be in strict correspondence with the powers centred in the nervous masses of the body, or in that arrangement of nervous particles which represents or replaces them.'
• Which consists of fishes, reptiles, birds, and mammals. The volume of the brain is proportionally larger as the animal occupies a inore elevated scale in the rank of life.
Now more than this need not be stated here, as our object is only to press the consideration of organic distinctions. The reader however will not forget that in the Theory of Transmutation it is held that there has been a gradual change from the lower forins up into the vertebrated class; indeed, without this supposition the Theory would be as much at a stand-still, as we have seen it to be at the starting-point, where Mr Darwin fairly acknowledged that he could not account for the first Transformations. In his Theory, however, creatures have been transformed from the first spore of a sea-weed into the lowest Protozoa, from the Protozoa to the Mollusca and crustaccan—and then, by some happy leap, into the vertebrated animal. But to this we reply that an animal must either possess the vertebral column, or be without it; and that if it has the vertebral column it has the brain, and the whole nervous system in a new arrangement, and for higher purposes of life. If therefore the transmutation has ever taken place, it has been an immediate operation, that is, an operation without any intermediate delay, it has not been effected in millions of ages by Natural Selection, but it has been done at once. The vertebral column has been formed for the occasion; and this, in other words, is an act of creation.
Now in this particular point Mr Darwin has already met us, by acknowledging more than we ever could have expected from him, for he has told us that the common first ancestor of all vertebrated animals* had many vertebræ.
* In one passage Mr Darwin has described our common prototype in a way to suggest the idea of the great sea-serpent. “It may be inferred that all vertebrate animals having true lungs have descended by ordinary generation from an ancient prototype, of which we know nothing, furnished with a floating apparatus or swim-bladder' (210); this coupled with the many vertebræ' of the grcat prototype brings our venerable sire into close approximation with the sea-serpent. If this disputed creature should be caught some day, we may live to see the great prototype's skeleton in the British Museum.
There was therefore no violation of the distinction of organization laid down by nature in this case; the first vertebrated animal did not pass by slow degrees from the lower form of life into the higher, but was made or created the first ancestor of all vertebrated animals that have ever since existed.
The Transmutationists having made this concession must abide by the consequences.
The lacteal provision for the nurture of their young er. hibited in the mammalia is a broad mark of distinction within the section of vertebrated animals. The reptiles are thus widely separated from the mammiferous animalsay a crocodile from a sow; and the whale, which suckles its young, from all the fishes of the sea. This, in fact, tells us a whale is not a fish. Earth, air, and water hare their mammiferous animals; in the air we find them among the bats, and on the earth we see them everywhere. This provision is a physical and even moral advance in animated nature, for amongst the animals thus furnished man himself takes his place; and wherever the mother's breast is, there is there a strong parental affection for the offspring.
The fishes and the reptiles * abandon their eggs and leave to nature their future destiny; the whale is passiouately attached to its young, and will brave every danger
* There are in the reptilia both viviparous and oviparous species, but the fætus in the former has no attachinent to the womb, and the eggs in the latter are hatched by extraneous warinth; the young, after exclusion, receive no parental care or tuition in any species of the class.'-Owen.