284 THE ZOOLOGIST. 



indeed movement of any kind to the left, was eliminated from 

 the succeeding trials, with the exception of the first trial on the 

 third day, when an abortive high-speed random flight of a few 

 centimetres to the left was once observed. High-speed random 

 flights to the right frequently recurred in the subsequent trials. 

 The experience demonstrates the ease with which the Wasp 

 acquired and retained " direction." Not so, however, the forma- 

 tion of the new motor-habit in all its details. Eight more trials 

 were required to bring the new habit towards a fair degree of 

 perfection, and the factors of the learning process were obviously 

 different from the high-speed random flight. 



In the third trial (the second was abortive) the Wasp, after 

 hovering before and walking all over the plug, drifted slowly to 

 the right, head-on to the clay face, and alighted to explore every 

 blind pocket in the clay in the plane of the random flights of 

 the first trial. In this way she arrived at aud entered the 

 rabbit-burrow. In the following trials she spent less time in 

 examining the plug and gradually reduced the number of blind 

 pockets to be explored on the way, until at the seventh trial the 

 examination of these pockets was entirely eliminated for good. 

 The ninth trial was distinguished by the appearance of a new 

 attitude. While drifting to the right from the plug to the 

 rabbit-burrow, the Wasp no longer squarely faced the clay, but 

 inclined the long axis of the body obliquely to the right, so that 

 the head looked half towards the bank and half towards the 

 rabbit-burrow. In the tenth trial the Wasp, at first, drifted 

 laterally to the right in front of the clay, and then, when half-way, 

 abruptly turned at right angles and flew, head-on, at normal top 

 speed into the rabbit-burrow. The plug was now almost a sufficient 

 stimulus to release the requisite movements leading to the rabbit- 

 burrow, and the sweeping curve of the air-line, followed in all 

 the later trials from the plug into the rabbit- burrow, was well 

 established. 



In most of the trials on the third day, a short reaction to the 

 plug induced the quick curving flight into the rabbit-burrow. 

 Several of the trials given on this day showed in the time records 

 apparent lapses on the part of the Wasp. These were due to 

 the necessity of renewing or remodelling the plug of clay used 

 to stop the tunnel. Interference with or renewal of the plug 



