262 Organic Physics. [March, 
out of previously absorbed water. This process, which is quite un- 
like muscular action, it is not necessary to here describe. Itis — 
sufficient to know that it results froma change in the character — 
of the cell protoplasm, which is instigated by external irritation — 
The final subject to be here examined is the chemical result of 
this continued oxidation. Degraded organic products must be 
continually formed. In the gland cells these take the character 
of special secretions. In the muscles urea is a marked product. 
But in all cells protoplasm must be reduced, and the most general 
products of this reduction seem to be the fats, and possibly the 
starches. Animal fat is doubtless partly derived from plants, but | 
must also be largely of animal origin. In efforts to explain its 
appearance most anatomists incline to the opinion that clear pro- — 
toplasm contains invisible or dissolved fat, and that this fat sub — 
sequently loses its solubility, and becomes visible as granules or 
globules. Such is the opinion of Sachs, Kolliker, Rindfleisch 
and others. But this does not explain its origin. It simply in- 
dicates the fact that fat granules constantly appear, with no evident — 
source. Rindfleisch declares that there is no question but that 
this fat originates in the interior of the cells. Voit shows thet 
fatand milk are formed from albuminous matters, and not from 
non-nitrogenous principles. Beale describes “ milk as a dissolved 
organ of the body, and not a simple filtration from the blood. 
He elsewhere ascribes the fatty granules of the cell to death of the 3 
protoplasm. Other authors might be quoted if necessary, but the 
is an intimate mixture of albumen and fats, as some aut 
ieve. l 
In all active animal cells minute granules appear. If nutrition 
be checked these increase in size, and plainly indicate their fatty 
nature. In cases of fatty degeneration, or the production of HE 
ordinary fat cells, the conversion of protoplasm into fat continue 
Finally the nucleus disappears, and only a spherical mass of se 
remains in the cells. The sebaceous glands are constantly ee 
pied in excreting it from the body. Occasionally the milk glands : 
act similarly. Their function is a sort of temporary fatty y 
generation of tissue. : 
ertain interesting experiments on starvation in plants a 
