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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 …

… 8 and 9. —Diagram indicating orientation of neurons for flexor and extensor muscles of third and fifth pairs of legs to explain galvanotropic reaction. (After Loeb and Maxvrell.) When the current goes from tail to head the cell bodies of the extensors of the third and of the …

… 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 …

All the phenomena of galvanotropism are, therefore, reduced to changes in the tension of associated muscles or contractile elements, as a consequence of which the motion of the organism toward one pole is facilitated, while the motion toward the opposite pole is rendered difficult. Galvanotropism is, therefore, a …

… 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 …

… vols. New York. — Stahl, E., 1884. Zur Biologie der Myxomyceten: Bot. Zeitung, XL, 146-155; 162-175; 187-191. — Statkewitsch, P., 1903. Ueber die Wirkung der Induktionsschlage auf einige Ciliata: Le Physiologiste Russe, III, 55 pp. — Id., 1903 a. Galvanotropism and galvanotaxis of organisms. Part First. Galvanotropism and

Radiation, discrimination from temperature effect, 615 ,, effect of electric, on Mimosa, 619 ,, identity of, in mature and growing organ, 435 ,, relation of, to stimulus, 95, 96, 97 ,, similarities of, between motile and growing organs, 437 See Chemotaclic-, Chemotropic-, Death-, Differential-, Galvanotactic-, Galvanotropic-, Geotropic-, Growth-, Heliotropic-, Inorganic-, Mechanical-, Phototropic …

… The real analogy for heliotropic reactions are forced movements and other tropisms, e.g., galvanotropism or geotropism-. Since forced movements (e.g., in Meniere’s disease) and galvanotropic reactions caused by a constant current through our head are not determined or accom¬ panied by special sensations, the same …

1 Abbott, J. F., and Lite, A. C.: Galvanotropism in Bacteria. Am. J. 2 Adams, G. P. : On the IsTegative and Positive Phototropism of the Earthworm Allolohophora foetida (Sav.) as Determined by Light of Different Intensities. Am. J. Physiol., 1903, ix, 26-34. 3 Allee, W. C. : An …

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 …

… Holmes states for the heliotropic reactions of this organism, that they are due to differences in the activity of the cilia on both sides of the organism and this ex¬ planation agrees with the actual observations of Bancroft on the galvanotropic reactions of Volvox.

… In galvanotropism the same general picture is presented by Palcemonetes and Amhlystoma when the anode is at the head end, the tonus changes involved being identical in the two conditions

… 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 …

A similar meclianism of galvanotropic conduct exists in Volvox & spherical, unicellular organism which is sur¬ rounded hy cilia on its whole surface. A definite pole of the organism is always foremost in all locomotions. This organism usually swims to the anode when in a galvanic field. Bancroft made …

… The Mechanism of Galvanotropic Orientation in 22 Banta, a. M.:' Experiments on the Light and Tactile Reactions of a Cave Variety and an Open Water Variety of an Amphipod Species. Proc. Soc. Exp. Biol, and Med., 1913, x, 192. 24 Barratt, j. 0. W.: Der Einfluss der Konzentration …

… 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 not difficult to suggest by aid of a diagram the arrangement of the elements in the central nervous system required to bring about the phenomena of galvanotropism just described for Palcemonetes. We take it for granted that the regular phenomena of anelectrotonus and cate- lectrotonus of …