. Carnegie Institution of Washington publication. Structure and Polarity of Electric Motor Nerve-Cell in Torpedoes. 247 The next experiment, on torpedo No. 3, was positive in its results. The force used was 543 times gravity for 1 minute. The plasmosomes were all moved by an anterior-posterior centrifugal force of this strength from varying positions, mostly ventral, to a position in a posterior arc of about 40 degrees. (See text-figure 6, zg.) In this arc the nuclear wall is so flat with respect to the direction of the force exerted that it makes very little difference in what portion of such
. Carnegie Institution of Washington publication. Structure and Polarity of Electric Motor Nerve-Cell in Torpedoes. 247 The next experiment, on torpedo No. 3, was positive in its results. The force used was 543 times gravity for 1 minute. The plasmosomes were all moved by an anterior-posterior centrifugal force of this strength from varying positions, mostly ventral, to a position in a posterior arc of about 40 degrees. (See text-figure 6, zg.) In this arc the nuclear wall is so flat with respect to the direction of the force exerted that it makes very little difference in what portion of such an arc a plasmosome comes to rest, just as the natural force of orientation always brings it into the arc xy (text-fig. 6), but into any part of that arc. Thus, in text-figure 6, we have a diagram representing the outline of a nucleus of one of the electric motor nerve-cells with one arrow representing the direction of the force of gravity and another rep- resenting the centrifugal force as applied in this experiment on No. 3, as well as in other ex- periments where greater forces were employed. In such a cell the normal po- sition of a naturally ori- ented plasmosome is at 1-a, although it may rest in any part of the arc xy, as at 1-6 or l-c. When centrifugal force is ap- plied of sufficient extent to change the position of the plasmosome it moves in the direction indicated by the two-barbed arrow until it comes to rest on the arc zg. If the plasmosome starts from 1-a, or even from a more dorsal position, as 3-a, it will come to rest well in the ventral part of the arc zg or at 2-a. In this case it rolls along the curved outline of the nucleus until the first part of the arc is reached at g, when it stops because the angle is too obtuse. If it starts from a median position, as at 3-6, or from any position on a median line with reference to the centrifugal force applied, as at 3-e or 3-/, it will come to rest in the center of the arc zg at 2-6. If it lies in the dorsal half of
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