...the theory of ' forced orientation.' As is well known, the earth worm is negatively phototactic. " As the worm crawls it frequently moves the head from...body ; it then swings the head from side to side, or it draws it back and forth several times, and extends again. If in so doing it encounters a strong...

...p. 99). The precise behavior of the earthworm in becoming oriented to light is described as follows: "As the worm crawls it frequently moves the head from side to side as if feeling its way along. If a strong light is held in front of the worm, it at first responds by a vigorous contraction...

...p. 99). The precise behavior of the earthworm in becoming oriented to light is described as follows: "As the worm crawls it frequently moves the head from side to side as if feeling its way along. If a strong light is held in front of the worm, it at first responds by a vigorous contraction...

...it follows up the right movements." The earthworm was found to orient itself in a similar manner. " If a strong light is held in front of the worm it...and forth several times, and extends again. If in doing so it encounters a strong stimulus from the light a second time it draws back and tries once...

...out; but these usually appear as parts of a more general behavior picture. Holmes describes it thus: As the worm crawls, it frequently moves the head from side to side as if feeling its way along. If a strong light is held in front of the worm, it at first responds by a vigorous contraction...

...out; but these usually appear as parts of a more general behavior picture. Holmes describes it thus: As the worm crawls, it frequently moves the head from side to side as if feeling its way along. If a strong light is held in front of the worm, it at first responds by a vigorous contraction...