LOCOMOTIONS OF SURFACE-FEEDING CATERPILLARS. 143 



scented band, was to cross the gap between / and c and proceed 

 along cba to the lower portion of the post. Roaming at random 

 to and fro over the maze, pausing from time to time to make 

 exploring movements, retreating whenever it encountered a 

 scented band, sooner or later the caterpillar would usually cross 

 the gap between / and c and escape along cba to the lower post 

 and thence to the ground. Occasionally a caterpillar would drop 

 from the maze to the ground; in a few cases, after a few move- 

 ments, it would rest indefinitely in one place; in less than one 

 per cent, of the cases, the insect would escape across the scented 

 band. In these cases the band had not lost its odor; for immed- 

 iately thereafter another caterpillar, on reaching the same band, 

 would retreat. Even the same caterpillar, on being replaced 

 between the bands, would retreat from the band across which it 

 had recently escaped. 



A transcription of the record of one experiment will illustrate 

 the behavior under these conditions. The specimen is a tent- 

 caterpillar and the maze is arranged as in Fig. 2. The bands 

 G and H are moistened with oil of cedar. It is between three 

 and four in the afternoon and the maze is situated in the shade of 

 trees; but, here and there, blotches of sunlight touch it. The 

 caterpillar, which is placed near j, ascends the post until it 

 reaches the band G. There it makes exploring movements and 

 retreats down the post. On reaching j, it partly explores it, 

 then returns to the post, and continues downward to e. It 

 moves along e to/, makes a few exploring movements, descends 

 / and crosses the gap to c. Returning to / it ascends f to e and 

 then retreats to the lower end of /. After making exploring 

 movements, it crosses the gap to c, moves along cba to the lower 

 portion of the post and thence to the ground. The caterpillar 

 is returned to its former position between the two bands. It des- 

 cends to the band H, makes exploring movements and retreats 

 up the post. It mounts j, and, after making exploring movements, 

 returns to the post and descends to H. After making exploring 

 movements, it encircles the post and ascends to e. It mounts 

 e, then returns to the post and continues upward to the band G. 

 After making exploring movements, it descends to j, makes 

 exploring movements, returns to the post and continues down- 



