Hence these also must feed on organic matter; not, indeed, on starch, dextrine, and protoplasm, but on decaying organic matter. In these plants the organic matter is taken up in some form intermediate between the planes No. 3 and No. 2. The matter thus taken up is, a portion of it, consumed with the formation of CO2 and H2O, in order to create force necessary to organize the remainder. To illustrate: Matter falling from some intermediate point between No. 2 and No. 3 to No. 2, produces force sufficient to raise matter from the same intermediate point to No. 3; a portion runs to waste downward, and creates force to push the remainder upward.
5. Growth of Green Plants at Night.—It is well known that almost all plants grow at night as well as in the day. It is also known that plants at night exhale CO2. These two facts have not, however, as far as I know, been connected with one another, and with the principle of conservation of force. It is usually supposed that in the night the decomposition of CO2 and exhalation of oxygen are checked by withdrawal of sun light, and some of the CO2 in the ascending sap is exhaled by a physical law. But this does not account for the growth. It is evident that, in the absence of sunlight, the force required for the work of tissue-building can be derived only from the decomposition and combustion of organic matter. There are two views as to
