[268] Osterhout, W. J. V., Bot. Gazette, 1906, xlii., 127; 1907, xliv., 257; Jour. Biol., Chem., 1906, i., 363.

[269] Ostwald, Wo., Arch. f. d. ges. Physiol., 1905, cvi., 568.

[270] Loeb, J., Jour. Biol. Chem., 1915, xxiii., 423.

[271] Loeb, J., Jour. Biol. Chem., 1905–06, i., 427.

[272] Meltzer, S. J., and Auer, J., Am. Jour. Physiol., 1908, xxi., 400.

[273] This theory was first expressed by the writer in Am. Jour. Physiol., 1900, iii., 434.

[274] Henderson, L., The Fitness of the Environment. See also Michaelis, L., Die Wasserstoffionenconzentra­tion. Berlin. 1914.

[275] Loeb, J., Der Heliotropismus der Tiere and seine Übereinstimmung mit dem Heliotropismus der Pflanzen. Würzburg, 1890 (appeared in 1889).

[276] Loeb, J., Biol. Bull., 1915, xxix., 50.

[277] Cuénot has proposed the term preadapta­tion for such cases and this term expresses the situa­tion correctly. Cuénot, L., La Génèse des Espèces animales. Paris, 1911.