THE CYCLE OF LIFE 19 



be seen to be appreciated. The caterpillar begins 

 to spin from its mouth fine white silken fibers, 

 not unlike a spider's thread. The fore feet are 

 brought into use a little in drawing ont the thread to 

 the proper length. A cushion about two-twenty-fifths 

 of an inch in diameter is constructed of this material. 

 Strengthening threads are woven over and about this 

 pad, making it doubly secure in its position. To this 

 cushion the bodv is firmlv fastened by means of the last 



t/ / </ 



pair of prolegs. The caterpillar frequently tries its 

 " hold " before fixing itself. Should the silken founda- 

 tion not feel firm enough for the responsibility about 

 to be imposed, the larva releases its grip, turns around 

 and reinforces the cushion with additional fibers. 



A firm hold is then taken with the anal prolegs; the 

 caterpillar rests head upward, with the body slightly 

 contracted. After a moment it turns the head and 

 thorax to one side as far as possible, fastens a thread of 

 silk to the supporting object ; then, bending the head 

 backward at almost right angles to the body, it carries 

 the thread slowly by short jerks to the opposite side, 

 fastens it securely, and brings back another thread in 

 the same manner to the starting-place. This is repeated 

 until fourteen or fifteen threads form a loop in front of 

 the head. Into this the head and five segments of the 

 body are thrust, allowing the band to slip into the 

 groove between the fifth and sixth segments. The body 

 now hangs head uppermost in the silken loop, with the 

 caudal extremity clinging to the silken pad. The caudal 

 extremity is the only part of the body in contact with 

 the support. The caterpillar grows shorter, the seg- 

 ments appear swollen, the head curls forward. In this 



