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… 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 …

… Phenomena of galvanotropism can he observed also in infusorians. Thus Verworn*®® observed that when a current goes through a trough containing Paramcscia the animals will all move toward the cathode. The mech¬ anism of the reaction was discovered by Ludloff.®” The locomotion of Paramcecium is brought about by …

… 2 According to Kappers, the direction of outgrowth of nerve-tracts in the central nervous system is the expression of a directive electrical influence (analogous to galvanotropism) which he caUs "neurobiotaxis." Cf. Kappers, "On Structural Laws in the Nervous System," Brain, XLIV (192 1), 125, and earlier references …

… We found it advisable to increase the intensity very gradually by increasing slowly the resistance of a rheostat in a short circuit until the phenomenon of galvanotropism appeared most strikingly. When the current is too strong or too weak the phenomena are no longer clear. The com¬ mon …

… A. R. 1919. The Respiratory Rate of the Sciatic Nerve of the F rog in Rest and Activity, Jour. Gen. Physiol., I. 1923. Galvanotropism in the Earthworm, Jour. Gen. Physiol., V. Morean, T. H. 1897. ton in Allolobophora fotida, Arch. f. Entwickelungsmech., V. 1901 a. | es Determine Regeneration …

… The same author discovered that Euglena are galvanotropic when raised in acid media. On account of the asymmetry of their locomotor apparatus they are compelled to swim in a spiral, in most cases to the cathode, exceptionally to the anode. Bancroft showed that the orientation of these organisms …

… The galvanotropic facts men- tioned in Chapter XI. show most conclusively that in Crustaceans and Vertebrates there exists a relation between the orientation and function of certain motor elements, and a similar relation also finds expression in the experiments on the horizontal semicircular canal.1

… The case is similar to that of galvanotropism when the current goes through an animal lengthwise (see previous chapter). We must conclude from the observations of Holmes and Garrey, which will he discussed farther on, that if the head of a positively heliotropic animal is turned to a …

… This summarized statement is the usual form of the ''law of polar stimulation." It is important to note, however, that a polar action is seen in many other physiological processes occurring under the influence of the current; e.g., electrotonus, polar disintegration of cells, galvanotropic growth, and galvanotaxis …

… At that time, an influential view, championed by the physiologist Jacques Loeb (see Pauly, 1981), held that protozoan behavior was driven by various ‘tropisms’ (heliotropism, galvanotropism, chemotropism, geotropism, etc.). The concept of a tropism was inherited from the study of movement in plants, where it was observed that …

… 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 …

1 This explains the galvanotropic gatherings observed by Hermann, Blasius and Schweitzer, and others. position of the legs. In the third pair the tension of the flexors predominates, in the fifth the tension of the extensors. The animal can thus move off easily with the pulling of the …

… This must be taken into consideration in galvanotropic experiments. appendages, and the tail also, are stretched backward or dorsad to their fullest extent. This proves that the tension of the muscles that move those organs back- wards is greater than that of their antagonists. The shrimp can thus …

… Experiments on galvanotropism of ani- mals have proved that a simple relation must 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 …

… The flight of the moth into the flame is in reality only the result of a tropism, — heliotropism, which differs from galvanotropism chiefly in that the rays of light take the place of the curves of the current. The reader knows that certain plants when exposed to the …

… Similarly, cell mobility, including galvanotaxic movement of cells and galvanotropism in response to endogenous, global electric fields, is another key component of bioelectric pattern regulation. BETSE currently considers a fixed lattice of cells, which cannot move with respect to the environment. Cell and cluster shape changes in response …

… This relation is of interest in view of galvanotropic experiments, which we shall discuss later on. It is furthermore probable from v. Uex- kiill's experiments that the act of eating depends upon the integrity of the first central ganglion, while the second and third central ganglia are …

… I shall now be able to show further that the galvanotropic effects observed are all deducible from these. Incidentally, too, owing to certain special advantages afforded by growth-response, we shall be able to discover additional effects which could not have been detected by the mechanical response of …

… Mach noticed the same effect of falling to the side of tlie anode when a galvanic current was sent sidewise through fishes.^®'’ These galvanotropic motions are in reality for<*ed move¬ ments, and this has boon proved by direct observations. It was shown by Loeb and Maxwell®'*^ in …

… Our experiments on galvanotropism indicate the existence of a simple relation between the orien- tation of certain motor elements in the central nerv- ous system and the direction of the motions produced by their activity. This is supported to a certain extent by the experiments on the crura …