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… With the exception of a few individuals, which have in recent years fallen into the hands of physiologists who happened to be working on galvanotropism, no animal has ever had the chance to come under the influence of an electric current. And yet galvanotropism is a remarkably common …

… The algae of the species Volvox show heliotropism and galvanotropism. The investigations made by Holmes and myself upon heliotropism, as well as those of Bancroft upon the galvanotropism of these organisms indicate that the mechanism of these reactions in Volvox is the same and the degree of determinism …

Claparede raises the objection that the galvanotropic reactions are purely compulsory, while the heliotropic reactions are governed by the ''interest of the animal. "^ Such a view, however, is not supported by the facts. The reason whjheliotropism may occasionally, as we have seen, be of use, while galvanotropism has …

… This phenomenon we call galvanotropism. In galvanotropism the current lines or the current curves play the same role as the light rays in heliotropism. At those points where the current curves enter the cells^ a collection of ions takes place which influences the chemical reactions. The number of …

… A much more striking example is offered in the case of galvanotropism. Many organisms show the phenomenon of galvanotropism, yet, as the writer pointed out years ago, galvanotropism is purely a laboratory product and no animal has ever had a chance or will ever have a chance to …

… In order to prove this point we will turn to the phenomenon of galvanotropism. The galvanic current forces certain animals to move in the direction of one of the two electrodes just as the light forces the heliotropic animals to move towards (or from) the source of light …

1 That the mechanisms by which heliotropic and galvanotropic orientation is brought about are identical was shown by Bancroft in Euglena (Bancroft, loc. cit.). the forward motion is rendered easy, the backward motion is difficult. Hence it can easily move toward the anode, but only with difficulty toward …

… g., positive heliotropism — are found in organisms that never by any chance make use of them; and later that a great many organisms show definite instinctive reactions towards a galvanic current — galvanotropism — although no organism has ever had or ever will have a chance to be exposed to …

… This change in the position of the legs occurs when the animal is not moving at all, thus showing that the galvanotropic movements take place not because the animal intends to go to the anode, but that the animal goes to the anode because its legs are practically …

… It is, therefore, just as incorrect to assert that the hehotropic reactions are governed by the bio- ^ ' logical interests of the animal as that this is true for galvanotropism. We must, therefore, free ourselves at once from the overvaluation of natural selection and accept the consequences of Mendel …

… Experiments on galvanotropism of animals suggest that a simple relation may exist between the orientation of certain motor elements in the central nervous system and the direction of the movements of the body which is called forth by the activity of these elements. This perhaps creates a rational …