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Show tl4 HYPOTHESIS OF THE DEVELOPMENT OF tttill take place in some of the obscurer fields of creation, or under extraordinary casualties, though science prof~ sses to have no such facts on r~c01·d. It is here to be remarked, that such facts might often happen, and yet no record be taken of them, for so strong is the prepossession for the doctrine of invariable like-production, that such circumstances, on occurring, would be almost sure to be explained away on some other supposition, or, if present ed, would be disbelieved and neglected. Science, therefore, has no such facts, for the very same reason that some small sects are said to have no discreditable membersnamely, that they do not receive such persons, and extrude all who begin to verge upon the character. There are, nevertheless, some facts which have chanced to be reported without any reference to this hypothesis, and '\vhich it seems extremely difficult to explain satisfactorily upon any other. One of these has already been mentioned- a progression in the forms of the animalcules in a vegetable infusion from the simpler to the more complicated, a sort of microcosm, representing the whole history of the progress of animal creation as displayed by geology. Another is given in the history of the Acarus Crossii, which may be only the ultimate stage of a series of similar transformations effected b:-/ electric agency in the solution subjected to it. There is, however, one direct case of a translation of species which has been presented with respectable amount of authority.* It appears that, whenever oats sown at the usual time are kept cropped down during summer and autumn, and allowed to remain over the winter, a thin c.rop of rye is the harvest presented at the close of the ensuing summer. This experiment has b~en h·jed repeatedly, with but one result: invariably the secale cereale is the crop reaped where the avena sativa, a recognised different species, was sown. Now it will not satisfy a strict inquirer to be told that the seeds of the rye were latent in the ground, and only superseded the <.lead product of the oats; for if any such fact were in the case, why should the usurping grain be always rye? Perhaps those curious facts which have been stated with regard to forests of one kind of trees, when burnt down, being succeeded (without planting) by other kinds, may yet be found most explicable, as this is, upon • See an article by Dr. Weissenborr.. -'n the New Seriel:l of" Ma· ga1.inc of Na1 ural Ilistury ," vol. i. p. 674. THE VEGETABLE AND ANIMAL KINGDOMS 115 the hypothesis of a progression of species which takes place unclcr certain favoring conditions, now apparently of comparatively rare occurrence. The case of the oats is the more valuable, as bearing upon the suggestion as to a protraction of the gestation at a particular part of its course. Here, the generative process is, by the simple mode of cropping down, kept up for a whole year beyond its usual term. The type is thus allowed to advance, and '\Vhat was oats becomes rye. The idea, then, which I form of the progress of organic life upon the globe-and the hypothesis is applicable to all similar theatres of vital being-is, that the simplest and most primitive type under a law to which that of like-production is subordinate, gave birth to the type next above it, that this again produced the next higher, and so on to the very highest, the stages of advance being in all cases very small-namely, from one species only to another; so that the phenomenon has always been of a simple and modest character. Whether the whole of any sp€> cies was at once translated forward, or only a few parents were employed to give birth to the new type, must remain ~ndetermined; but, supposing that the former was the case, we must presume that the moves along the line or lines were simultaneous, so that the place vacated by one species was immediately taken by the next in succession, and so on back to the first, for the supply of which the formation of a new germinal vesicle out of inorganic matter was 'alone necessary. Thus, the production of new forms, as shown in the pages of the geological record, has never been anything more than a new stage of progress in gestation, an event as sirnply natural, and attended as lit. tie by any circumstanres of a wonderful or startling kind1 as the silent advance of an ordinary mother from one week to another of her pregnancy. Yet, be it remembered, the whole phenomena are, in another point of view, wonders of the highest kind, for in each of them we have to trace the effect of an Almighty Will which had arranged the whole in such harmony with external physical circumstances~ that both were developed in parallel steps-and probably this development upon our planet i8 but a sample of what has taken place, through the same cause, 1n all the other countless theatres of being which are susvended in space. This may be the proper place at which to introduce the |