SOME SUGGESTIONS FOR THE STUDY OF INSECTS. 157 



dangles in the air while we search the ground or amongst 

 the leaves for the caterpillar we are sure we saw. The 

 thread is extremely slender, and we may handle the bushes 

 so roughly that it is broken ; it will not stand all sorts of 

 usage, but in the main it serves its end. 



The caterpillar hanging by its thoracic feet and jaws upon 

 its cord commences the return journey, and its progress up- 

 ward is well worth watching (Fig. 55 4 ). With hind body 

 stiffened out behind, and head alternately thrown back and 

 then forward to grip the silken cord by the jaws, the 

 acrobat at length reaches the shelter of its leaf. Pupils 

 should be made to observe the whole process. The cater- 

 pillars can be got to fall off the end of a pencil and climb 

 up again. 



There is no doubt that this habit is effectively protec- 

 tive, and that caterpillars which are able to do this, in a 

 large number of cases will escape capture by their bird 

 enemies. Our particular caterpillar is a well protected 

 type in this and in other ways, as we shall note further on. 



Sometimes the creature falls to the ground. What 

 happens ? Hold one in the hand and cause it to fall 

 on the table. It doubles itself, head close to tail, but 

 with the last segment projecting, and lies motionless 

 (Fig. 55 s ). This is a quite definite piece of behaviour. 

 Many other caterpillars do the same kind of thing. They 

 have learned, somehow, the advantage of keeping still; 

 that movement attracts attention, and that to be seen may 

 mean death. Many animals through stress of life have 

 discovered this. Our caterpillar in a short time if undis- 

 turbed will slowly turn over and proceed to crawl away, 

 but there are some creatures which lie still so long that 

 they are apt to be regarded as dead. The larva of the ant 

 lion, a predaceous insect feeding on ants, is an adept at 

 this kind of " death-feigning." The fox is credited with 

 the same kind of behaviour. 



The pupils should add another to their series of draw- 

 ings, that of the caterpillar as it lies folded motionless 

 upon the ground. 



Our caterpillars are remarkable for the variety of ways 

 in which they are protected from attack. Besides the ways 



