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When therefore life was to be exalted into a more vigorous manifestation, the vertebral column was formed, a case aud 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 immediate 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.'
0 Which consists of fishes, reptiles, birds, and mammals. The volume of the brain is proportionally larger as the animal occupies a more 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 forms 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 crustacean—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 vertebrae.
* 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 vertebrae' of the great 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 exhibited in the mammalia is a broad mark of distinction within the section of vertebrated animals. The reptiles are thus widely separated from the mammiferous animal— say 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 have their mammiferous animals; in the air we find them amonsr 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 passionately attached to its young, and will brave every danger for their protection. In the manifestation of this passion we see something that deeply interests us, we begin to feel that there is some communion between us and animals. The animal whose breasts bind it with ties of affection to its little ones, is, in a point that touches us nearly, very like ourselves.
* 'There are in the reptilia both viviparous and oviparous species-, but the foetus in the former has no attachment to the womb, and the eggs in the latter are hatched by extraneous warmth ; the young, after exclusion, receive no parental care or tuition in any species of the class.'—Owen.
Amongst select classes of the vertebrated animals the mother is supplied with milk, but amongst animals of a widely different character the parental affection is, nevertheless, elicited in strength, as amongst the birds and some of the insects. The structure'of these creatures does not admit the fcetal growth of the young and the corresponding secretion of milk; but by other ordinations of nature the young animals whose early existence requires aid and protection, find it in the affection of their parent, for if Nature does not herself nurture and educate the progeny, she arranges* that the parent animal shall administer to all the needs of the helpless offspring.
Now amongst the mammalia this great distinction is an obstacle to transition from the other vertebrated animals, obviously arranged by general plan and design. That an animal without milk and without care for its offspring, should acquire milk and be attached to its young, is as impossible as to change the structure of its heart, or to alter the convolutions or proportions of the brain.
* This is more markedly shown to us in the habits of the ostrich. The young birds hatched in the torrid zone of Africa are left to take care of themselves, as the heat is sufficient for their growth, and they can find their own food; but towards the Cape, where the climate is less warm, the mother ostrich watches over her young with the greatest care, and attends to their wants. 'Aussitot que les jeunes autruches sont ecloses, elles sont en etat de marcher, et meme de courir et de chercher leur nourriture; en sorte que dans les zones torrides, ou elles trouvent le degre de chaleur qui leur convient, et la nourriture qui leur est propre, elles sont emancipees en naissant, et sont abandonnees de leur mere, dont les soins leur sont inutiles: mais dans les pays moins chauds, par exemple, au Cap de bonne esperance, la mere veille a ses petits tant que ses secours leur sont necessaires, et partout les soins sont proportionnes aux besoins.'—Button.
The general organic distinctions to be observed in the vcrtebrated animals cannot be better expressed than in the words of Cuvier:—
'Vertebrated animals offer four grand subdivisions or classes characterized by the sort or the force of their movements, which themselves depend on the quantity of their respiration—observing always that it is from respiration that the muscular fibres derive the energy of their irritability.
'The quantity of respiration depends on two factors: the first is the relative quantity of the blood which in any one instant is presented to the organ of respiration; the second is the relative quantity of oxygen which enters into the composition of the circulating'fluid.
'The quantity of blood which is respired depends on the disposition of the organs of respiration and of those of circulation.
'The organs of circulation may be double, so that all the blood which arrives from the various parts by the veins should be obliged to go for circulation in the organ of respiration before it returns to the parts by the arteries; or they may be simple, so that one portion only of the blood which comes from the body should be obliged to pass by the organ of respiration, whilst the rest returns to the body without having gone for respiration.
'This last case is that of reptiles. Their quantity of respiration, and all the qualities which depend on it, vary according to the proportion of the blood which is sent to the heart at each pulsation.