BEHAVIOR OF THE COMMON ROACH. 355 



spending side of its body. Some roaches pause at practically 

 every point on the side of the runways and explore upward, 

 outward, and downward with their antennae, and then, retracing 

 their steps, explore the same territory over and over again; yet 

 other roaches pause only here and there to make explorations. 

 Some roaches, and this is especially true of roaches from ten to 

 fifteen millimeters in length, move along part of the time on 

 top of the maze and part of the time suspended from its edge. 

 Had the maze bee.. Constructed of cardboard these same roaches 

 would have made part of their journey suspended from the 

 bottom of the maze. Some roaches pause from time to time to 

 make their toilet : others never once pause for such purposes. 

 Some few roaches, after making several attempts to find an exit 

 from the maze, stop trying and act as though they have given 

 up all hope of succeeding; others, after failing to find a means of 

 escape, attempt to jump to freedom. These jumping roaches 

 were always returned to the maze at the point from which they 

 jumped. After one to many jumps had proved failures, these 

 roaches usually stopped jumping and proceeded to solve the 

 maze in the right way. These variations were not inflexible 

 instinctive responses, for the same roach did not always behave 

 the same way at all trials. 



JUMPING ACTIVITIES AND WILL. 



Although this jumping activity results in a plunge into the 

 water, it resembles neither the dashes into the water made by a 

 roach on being placed on the maze for the first time nor the falls 

 into the water by roaches that are trying to run the maze. The 

 roach pauses at the edge of the maze and explores outward and 

 downward with its antennae. It acts as though it were trying to 

 see something at a distance and then, after a pause, makes what 

 an athlete would call a broad jump. Many roaches displayed 

 this jumping behavior, but some were more prone to jump than 

 others. I experimented with one roach which, on its initial trial, 

 made ten jumps from the maze; usually from a different point 

 each time. This jumping attitude is so characteristic that one 

 can always predict when a roach is likely to jump. I say likely 

 to jump instead of going to jump; because, after a roach has once 



