THE FALL WEB WORM — SNODGRASS. 407 



themselves as masters toward slaves. But they soon tire of case and 

 luxury, and a spirit of restlessness takes hold of them. The old home 

 no longer has attractions; the unknown world beyond is calling. So, 

 one by one, the furry giants wander off, each choosing a route to his 

 own liking. From ardent communists they have changed to arrogant 

 individualists. They run rapidly with a pronounced humping move- 

 ment of the back, first noticed in Stage V, a trait characteristic of the 

 woolly bear caterpillars, to which the webworms are closely related. 

 But the full grown webworms are not gentle like those furry creatures ; 

 they are proud and irritable and very much resent being disturbed or 

 handled. When one of the travelers is stopped in his course by human 

 fingers he whirls about, humps and kicks, spits out a drop of greenish- 

 brown liquid from his mouth, and drops from the tree. During this 

 wandering stage the webworms may be seen traveling all over trees 

 and fences far from home, and most evidently enjoying their new free- 

 dom. They feed along the way on whatever tree or bush they hap- 

 pen to be upon when hunger overtakes them. Yet they do not travel 

 like one out purely for pleasure. They go about with a nervous 

 hurry, and are ever stopping to examine chinks, corners, and crevices 

 as if such places held a special interest for them. This curiosity 

 grows upon them and develops into a desire for concealment, which 

 at last becomes paramount. In fact, the real purpose of the final 

 wandering period in the webworm's life is the finding of a suitable 

 shelter for its next approaching stage, that of the chrysalis or pupa. 

 The pupa is the stage in insects where the worm is made over into 

 the final adult form. When the webworm caterpillar feels that its 

 time of change is near, it selects some retreat beneath a piece of 

 loose bark, in a corner or under any ledge of a fence, beneath rub- 

 bish, leaves, or stones lying on the ground, or it even burrows below 

 the surface of the earth. Wherever it decides to locate, it there pro- 

 ceeds to spin and weave a loose cocoon of silk about itself. But. as 

 it bends and twists at its work, its long hairs become rubbed off 

 against the enveloping network and are enmeshed in the threads, 

 with the result that the fabric of the finished cocoon is half silk 

 and half wool. If the cocoon is constructed on the ground or beneath 

 the surface, particles of earth become woven into its texture and, in 

 this case, the denuded webworm must wear a penitential vestment 

 worse than the traditional one of sackcloth and ashes. Most any 

 other caterpillar would evade this hardship by secretly lining the 

 thing with a coating of soft silk; but the webworm must have had 

 its fill of spinning earlier in its career, for it now endures anything 

 rather than weave more than a mere covering for itself. Some indi- 

 viduals avoid the spinning altogether by crawling into deserted 



