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coercenda, quia ex divinorum et humanorum, male sana admixtione, non solum educitur, philosophia phantastica, sed etiam religio hæretica.” We have only endeavoured to illustrate and point out the consequences of the statement of Baron Cuvier, “ that the order which the cosmogony of Moses assigns to the different epochs of creation, is precisely the same as that which has been deduced from geological considerations.” We have been guilty of no improper mixing up of divine and human things. We have examined the meaning of the terms in the first chapter of Genesis, in consistency with the acknowledged rules of criticism, and only by the light contained within itself, or that thrown upon it by the other books, in the same language with which it is associated. The human science we have not extracted from any part of the Holy Scriptures; we have taken it simply as we find it in the works of eminent geologists. As the latter is not a philosophia phantastica, but a deeply interesting science, constructed by that method of careful observation and cautious induction, which Bacon was himself the first to recommend; so neither can the sense of the Scriptures present to us a religio hæretica. If our science, thus constructed, and our religion speak so obviously the same language, as we have seen they do on one important point, what else, in the strictest application of Bacon's philosophy, can we deduce from the circumstance, but that both are certainly true ?
It does not come under our present subject to discuss the his torical and moral evidences of the divine revelation of the Scriptures ; but both are so full, even to overflowing, and impose upon us so many insuperable difficulties, in the way of our being able to account for the quality and consistency of these remarkable books, excepting on the ground which has been all along assumed by themselves, that they are of more than human origin, that in estimating the accuracy of any part of the matters contained in them, the fastidiousness of human science appears to be carried to an unreasonable extent, not to take these evidences into calculation. In this country, where for a long period we have had the Scriptures in our hands as a popular book, they among us who have been the most eminent for human learning and science, and whose fame has been in every view the most unsullied, have been so convinced by the force of
these evidences, that they have in general been the most strenuous defenders of revelation.
Will not human science, then, condescend to borrow some light, to direct the steps of its own inquiries, from a record, the accuracy of which it has itself proved, and which is supported by other proofs of the highest order? or, what should we say to the illustrator of the relics of Pompeii and Herculaneum, who should reject the light thrown on them by the Letters of Pliny, authenticated as these are by the existing remains of the buried cities, as well as the historical evidence which is proper to themselves?
Among the questions which geology is at present attempting to solve, is that of a different temperature of some regions of the earth at a remote age. The discoveries of Pallas and Adams, of a rhinoceros and elephant in Siberia, having coverings of hair fit to protect them from the cold of the northern regions, would seem to decide the question, so far at least as to shew, that there has been no change of temperature since the creation of animals. But the question does not seem yet so satisfactorily answered, so far back as to the age of the creation of vegetables. Does not the statement in Genesis, that the establishment of our present days and seasons was intermediate between the creation of vegetables and that of animals, give us a clew to direct our path in the inquiry ?
On the Fundamental Types of Organization. By G. R. TRE
VIRANUS, M. D. &c. The doctrine of organization is founded on comparative anatomy, or the systematic distribution of living bodies, and on organic chemistry. It is not to be expected that we are to give here any thing but a mere outline of these sciences; a few landmarks, which I think have some pretensions to novelty, and are more correct then those which have been hitherto most generally admitted.
We can arrive at no mutual understanding in biology until accurate definitions are given of the classes, families, genera, and species of living beings. Ever since natural history has
been something more than a mere crude digest of unconnected facts and observations, philosophers have constantly endeavoured after the discovery of an arrangement in which the objects of their inquiries should be linked after their natural affinities ; while, at the same time, the characters of its subdivisions should possess the utmost simplicity, by being derived from a single system of organs. It may, in a manner, be compared with the philosopher's stone, whether he merely resort to such an arrangement for the purpose of discovering the name of an unknown animal or plant, or whether, with higher views, his researches enter deep into the philosophy of nature. With the first object only in view, external characters alone may suffice, and the more easy these are of detection, the better are they fitted for their purpose. The bond of natural affinities is quite subordinate to this primary object. But if his object be of the other description, the characters may lie deep, and be of the utmost difficulty to discover. His arrangement will be the more perfect the more completely it expresses the sum of all the external and internal structural differences, and the more uniform the parts are from which the characters are taken.
Of late years systems have been constructed upon the last of these principles. But their bases have been always such as I cannot admit. One of these is the principle, That all higher formations include those lower in the scale ; the most perfect organs in the former having already existed in the latter, but in their undeveloped state ; that there is one universal type, only modified in the degree of its development. There is much, both of truth and of error, in all this. It is true that every organized being advances from the simpler to the more compound in its progressive growth, and that the early stages of the life of an animal high in the scale present many points of similarity with the perfect state of another lower in the series. But these resemblances hold merely in external relations, and the numerous points of difference can by no means be overlooked.
The foetus of the inammalia and of birds is an aquatic animal, which respires not by means of lungs, and as such has a simple circulation like a fish. But in all other respects its circulating system is constructed upon a totally different principle from a fish. The apparent analogy vanishes upon a closer inspection.
The brain of the fætus of the mammaļia apparently resembles that of the other three vertebrated classes, as the tubercula
quadrigemina of the former, like the posterior hemispheres in the latter, exceed in volume all the other parts. But these posterior hemispheres contain parts which have nothing in common with the tubercula quadrigemina. In the early states of mammalia and fishes there are fissures in the sides of the neck which are somewhat similar to the external branchial orifices of the larva of the frog, tod, and salamander. But the resemblance is merely external. The fissures conduct to no true gills, but to certain small vacuities possessed by the embryo of fish in its early states. There is therefore nothing but a mere general analogy in the development of the vertebrata.
All analogy ceases whenever we attempt a comparison between the foetus of the latter with the perfect avertebrata. They have no range of ganglia along the abdominal aspect of the body, but have a spinal cord. The circulation is, from the very commencement, totally different from that of the mollusca, crustacea, &c.; and the organs of sense are, from their first beginnings, quite dissimilar *.
But some have gone farther, and maintain, that the higher organs are nothing else than repetitions of the lower organs of the same organism. From which has arisen the doctrine of the “ Relative Importance of Equivalents,” &c., which have afforded scope enough to the imagination, but have contributed but little to the extension of our acquaintance with the essence of life.
In my opinion, the following principles must be laid down as the base of every inquiry into the relations between different living bodies, with respect either to the whole of their organization or their individual organs.
1. The rank of a living being is higher the more numerous are its points of contact with the external world, the more di
• Many other insuperable objections against the doctrine of the development of organic bodies upon one prototype have been brought forward by Baer, in his Beitrügen zur Kenntniss der niedern Thiere (Verhandl. der Kaiserl Acad. der Naturforsch. xiii. Abth. 2. p. 739, &c.), and in his Entwickelungs geschichte der Thiere, Th. i. p. 199. Weber has also very clearly expressed himself on the point in his edition of Hildebrandt's Handluch der Anatomie des Menschen (i. 125).
versified its excitability. The number of these points of contact increase with the advancement of the intelligence, which necessitates a proportionate increase in the variety and perfection of the several organs. The intellectual faculty is more perfect in man than in any other terrestrial existence. He, therefore, merely in an organic point of view, stands at the head of the scale of animals. But this does not oblige us to suppose that in him every organ has reached the maximum of its development. An important line of distinction must here be drawn between the organic sphere of the sensitive and of the simply organic life. With respect to the former class of organs man is decidedly at the head of all animals, but by no means in respect to the latter. His alimentary apparatus, for instance, is not nearly so complicated as in many other animals. Between him and the lowest existences there are many members, of which one cannot be said to occupy a higher place than another. One being is best adapted for one purpose, and another for a different purpose. They can only be placed in a linear series, by arranging them according to the type of some one of their organs.
2. An original form may be very easily supposed, out of which all living things are developed. This development is not in one but in several directions. Each of these principal directions again give rise to new subdivisions, so that the whole assumes somewhat of an arborescent form. Different twigs, however, of one of the branches often unite those of another higher or lower in the scale. In the midst of all these diversities, a general similarity persists between the various organisms and their several parts, which enables us to trace them up to a common fundamental form. No conclusions, however, can be drawn from the similarity of two forms, regarding their respective superiority or inferiority in point of development. Such similarity may result from the lateral concurrence of two forms derived from totally different twigs. Insects, for example, resemble the vertebrata in some of their organs, but are otherwise so different from them in all their parts, that this partial exception cannot be considered to result from a higher development of the form peculiar to insects. As in the higher animals, so we can likewise distinguish in the alimentary canal of insects, a se