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116 prolongations of cells, and as the transformation of the cells into fibres in the areolar tissue, takes place by a gradual acumination, it seems to me, for the present, more probable that they are hollow rather than solid. If we imagine the formation of the fibres from a cell to take place by the cell-wall growing more vigorously at two opposite limited spots than it does at any other part, we can then conceive that the division of these main fibres into branches, and their prolongation into fibrils, may be effected by the same process. The question as to the hollowness or solidity of these fibrils, is still less capable of being settled by observation than that with respect to the larger fibres. Analogy is in favour of their being hollow, and the minuteness of an object forms no limit to nature’s operations.

The splitting into fibres, which, as we have seen, pursues retrograde course from the branches towards the main fibres, and thence towards the body of the cell, might be illustrated in the following manner:—suppose that part of a glove which corresponds to the hand to be the body of a cell, and the fingers to be a fasciculus of fibrils. If the membrane situate in the angle between two fingers grow in the direction of the hand, the glove will at length be split into five portions. But a difficulty arises with respect to the fibre-cells of areolar tissue, which is, that the division into fibres advances from two opposite sides towards the body of the cell, and, therefore, the fibres of one side must ultimately correspond with those of the other. This, however, admits of no further explanation than the healing of the corresponding primitive fibres in the reproduction of nerves does. Meanwhile the above are only attempts to convey a clear idea of the results of my investigations, modes of representation which are susceptible of various modifications, provided they be not made to contradict the observations; the latter may be briefly summed up as follows:—cells, furnished with the characteristic nucleus, are present in the first instance, which become elongated on two opposite sides, more rarely on several sides, into fibres, and these are prolonged into more minute fibres. At a later period the principal fibres, and then also the bodies of the cells are split into fibres, so that a small fasciculus of fibrils, with a nucleus fixed upon it, remains in the place of the original single