It forms red crusts, is insoluble in cold water, but is decomposed by boiling water.
The original hypothesis of Baeyer suggested that the course of events is the following: the carbon dioxide is decomposed into carbon monoxide and oxygen, while water is simultaneously split up into hydrogen and oxygen; the hydrogen and the carbon monoxide unite to form formaldehyde and the oxygen is exhaled.
So long as food is supplied the living substance is the seat of transformations which are continually proceeding, being partially decomposed and again constructed, the new food being incorporated into it.
They are not decomposed by boiling alkalis, but on heating with hydriodic acid they split into their components.
The most suitable soil is a light, sandy loam enriched with well decomposed manure, in a rather moist situation.