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120 gelatine from it by boiling, none at least which has the property of gelatinizing. The integument was removed from a pig’s foetus measuring four inches in length, cut up into pieces, and steeped in distilled water for a day. It was then boiled for twenty-four hours. The last process caused it to crumble into small particles that clouded the fluid, in which also some large lamellae of epidermis floated. When examined with the microscope the epidermis exhibited the same structure as it did previous to being boiled; the nuclei in the separate cells were also distinct. A quantity of fibre-cells floated in the fluid in the same state as when they, in their recent condition, composed the entire cutis, that is to say, longish corpuscles extended at both extremities into somewhat long fibres. The cell-nucleus could still be distinctly recognized in some of them. Thus the process of boiling, which had not produced any effect upon the fibre-cells or the fibres issuing from them, had dissolved the connecting cytoblastema, by which they had been held together in the recent state. The fluid was then filtered. Acetic acid caused a precipitate which was not dispersed by an excess of acid. A solution of alum produced a much more copious precipitate, which, in like manner, was not redissolved by an excess of alum, or at least not completely. Tincture of gall-nuts caused a thick clouding, spirits of wine only a slight-one. Hydrochloric acid clouded the fluid, and an excess of acid did not render it clear again. These reactions accord with what Güterbock has called pyine, save that the clouding produced in the latter by hydrochloric acid, was redissolved by an excess of the acid. <A portion of the filtered fluid was evaporated almost to dryness, but even after twenty-four hours, there was no trace of the formation of a jelly observable. In order to separate the component particles of this, in all probability, still very heterogeneous fluid, in some degree from one another, some pure alcohol was added to that portion of it which had been so long evaporated, whereby a very copious precipitate was produced. This was separated by filtration and washing, first with pure alcohol, and afterwards with spirits of wine of 80 per cent. strength, then dried, and again dissolved in boiling water. Acetic acid and alum caused precipitates in this solution, which were not again dissolved