They are of importance, since the higher homologues are identical in many cases with the ptomaines produced by the putrefactive action of some bacteria on albumen and other related substances.
When exposed to air the latex gradually undergoes putrefactive changes accompanied by coagulation of the caoutchouc. The addition of a small quantity of ammonia or of formalin to some latices usually has the effect of preserving them for a considerable time.
We have thus an explanation of the occurrence of marsh gas and sulphuretted hydrogen in bogs, and it is highly probable that the existence of these gases in the intestines of herbivorous animals is due to similar putrefactive changes in the undigested cellulose remains.
Exudations and Rotting.The outward symptoms of many diseases consist in excessive discharges of moisture, often accompanied by bursting of over-turgid cells, and eventually by putrefactive changes.
The combined nitrogen of dead organisms, broken down to ammonia by putrefactive bacteria, the ammonia of urea and the results of the fixation of free nitrogen, together with traces of nitrogen salts due to meteoric activity, are thus seen to undergo various vicissitudes in the soil, rivers and surface of the globe generally.
Nevertheless, gangrene is nothing more or less than the putrefactive fermentation of an animal tissue still attached to the body.