CONTENTS. 



PAGE. 



Nature and Evidences of Physiological States, in 



Physiological States in the Protozoa (Stentor as a Type), . . .112 



Physiological States in the Lower Metazoa (the Flatworm as a Type), . 115 

 Changes in the Sense of "Tropisms" and other Reactions, . . 117 



Changes in the Sense of Reactions with Changes in the Intensity of the 



Stimulus, ............ 118 



Interference of Stimuli, . . . . . . . . . .119 



Spontaneous Movements, ......... 120 



Methods of Causing Changes in Physiological States, .... 120 



Nature of Reactions to Stimuli, . . 121 



Physiological States in the Behavior of Higher Animals as compared with 



those in Lower Organisms, ........ 124 



Summary, . . . . . . . . . . . .126 



no 



