learned, that the elongation of a shoot tends to proceed by jerks, rather than smoothly, is another indication that the phenomenon is not purely and simply a chemical one. We have abundant illustrations, however, among animals, in which we may study the temperature coefficient under circumstances where, though the phenomenon is always complicated by osmotic factors, true metabolic growth or chemical combination plays a larger role. Thus Mlle. Maltaux and Professor Massart64 have studied the rate of division in a certain flagellate, Chilomonas paramoecium, and found the process to take 29 minutes at 15ô¯ C., 12 at 25ô¯, and only 5 minutes at 35ô¯ C. These velocities are in the ratio of 1ã₤:ã₤2ôñ4ã₤:ã₤5ôñ76, which
Table of Contents
CHAPTER III THE RATE OF GROWTH
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