case the cytoblastema is fluid. Beneath the pus, in healing wounds, lie the granulations, composed of a firm cytoblastema, in which lie a quantity of cells. Henle thus describes the microscopical structure of granulations: “The most superficial part presents cells, which resemble the pus-granules, except that their nuclei are not broken down by acetic acid. In the deeper strata, the nuclei are very distinct, and the envelopes are polygonal, in consequence of mutual pressure. Wood has already drawn attention to their resemblance to epithelial cells. Deeper still the envelopes of the cells are found passing through all the gradual transitions of the fibres of areolar tissue, just as in the immature areolar tissue of the embryo. The first rudiments of these fibres are the longish nucleated corpuscles, which Güterbock observed, and compared to the cylindrical epithelium. Hence it follows, that the formation of new cells proceeds upon the surface of the granulations, and that the transformation of the latter into cellular tissue (cicatrix-material, narbensubstanz) proceeds successively from the bottom of the wound towards the surface.” As no gelatine can be obtained from the granulations by boiling, Güterbock thought that those fibres in the granulations and exudations which resemble the areolar tissue ought not to be regarded as the actual fibres of that tissue, but as merely those of fibrin. But, as we have seen above, the entire areolar tissue of the foetus also does not afford any gelatinizing gelatine; and since Henle observed a similar course of development in these fibres to that which I had pointed out in the areolar tissue of the foetus, we must regard them as the young fibres of that tissue (although they may differ from the mature tissue in their chemical qualities), and the granulations as nothing more than a primitive formation of areolar tissue.
A formation of areolar tissue similar to that in the foetus takes place also in exudations resulting from inflammation. R. Froriep (Klin. Kupfertafeln, llte Lief. Weimar, 1837, Th. lxi) had already observed that irregular granules, some of which seemed to be extended on one or both sides into thin fibres, existed in the exudation of pericarditis, in addition to the fibres resembling areolar tissue. ‘These elongated gra- nules of fibrin,” he continues, ‘* seem to be the commencements of the formation of the new mass of tissue, that is, the rudi-
