The assumption, however, that in a living system at the same moment when oxygen is removed from the neighborhood, let us say by a stream of nitrogen, no oxygen would be present and that in consequence every oxydative process must cease, contains so little probability that I have rejected it on various occasions.[218] The way in which irritability is lost in asphyxiation of the nerve likewise very clearly demonstrates the untenability of this view. The recent investigations of _Lodholz_[219] have shown that decrease of irritability takes place after a sudden displacement of all oxygen from the surrounding medium uniformly and gradually in the form of a logarithmic curve. If at the moment of oxygen withdrawal from the outer medium, metabolism became entirely anoxydative, the curve of irritability must under all circumstances show a sudden _steep decline_ at this point, and subsequent to this a further _slower_ decrease. For, as the oxydative processes constitute by far the _chief_ part in the energy production of living substance, the production of energy, and with this irritability, would undergo considerable loss at the same moment in which oxydative was replaced by anoxydative disintegration. The curve of decrease of irritability during the transition period from oxygen supply to oxygen withdrawal shows, on the contrary, a completely uniform course and it is not until later that a very slow decline takes place, which only after a prolonged time assumes increasing rapidity. But the assumption that at the moment when the supply of oxygen ceases, anoxydative breaking down could acquire such enormous dimensions that it furnishes just exactly the same amount of energy as was before supplied oxydatively, is a view which no one will seriously entertain. In connection with this I wish to call attention to the experiments of _Fröhlich_[220] in which he compared the time required for asphyxiation to take place in the nerves, when, on the one hand, the frogs had been kept several days previous to the experiment in temperature of 14–40° C., and on the other, in one merely a few degrees above zero. He found that the nerves of the cooled frogs required on an average twice or three times as long for their irritability to sink to the same degree as those of the heated frog, although during the experiment the same temperature was present in both. It was also shown that the asphyxiation period was prolonged up to a certain limit, depending upon the length of time the animals were kept at a low temperature. It would seem to me that these facts admit of no other explanation than that in a low temperature a greater amount of oxygen is stored in the nerve than in high temperatures. From the standpoint that from the moment of withdrawal of oxygen from without, disintegration likewise takes place exclusively anoxydatively, these facts would be completely incomprehensible. When, however, the assumption is made, and this