YELLOW-NECKED WORM — -LARVA DESCRIBED. 237 



may be left behind when this migration occurs, being so intently 

 occupied in feeding as not to notice the departure of their com- 

 rades. But on becoming aware of their solitary situation they 

 hasten after their associates ; and it is curious to observe the un- 

 erring accuracy with which they track and find them. On com- 

 ing to where a twig branches off, it is examined, the worm reach- 

 ing up it a third of its own length it may be, when it ascertains 

 that the brood is not upon that twig, and drawing back, it tra- 

 vels onward, until it reaches the identical twig up which its pre- 

 decessors have gone, and up which it at once mounts. The worm 

 would seem to have some instinct by which it is informed of the 

 direction in which its fellows have located themselves, or to 

 possess an acutenessof smell like that for which the dog is noted, 

 to be thus able to scent their footsteps. But when we come to 

 examine the road they have followed, with a magnifying glass, 

 we discover the clue which has doubtlessly served to guide them 

 in this journey. Stretched along upon the bark we find a mul- 

 titude of threads resembling the finest cobweb, so fine that they 

 are wholly invisible to the eye. These threads the worms spin 

 from their mouths wherever they go. And though so exceed- 

 ingly slender they possess a surprising degree of strength, it be- 

 ing sufficient to sustain the weight of the worm. Individual 

 worms sometimes when they are disturbed suspend themselves 

 in the air hereby. They are more apt, however, to drop them- 

 selves to the ground. Others, when annoyed, throw their heads 

 spitefully from side to side; but their most common resort, as 

 already stated, is to throw the extremities of their bodies up- 

 ward, and some will even bend themselves so far as to touch 

 their heads and tails together, their bodies thus resembling a 

 hoop or a ring. 



The Larvae are plump cylindrical shining worms, thinly clothed with long 

 soft white hairs . When young their ground color 

 is tawny yellow or sometimes tawny red; when ma- 

 4 . ture they are coal black. They have been described 

 as gradually changing to a darker color with each 

 change of their skin, but I think this is a mistake- 

 They remain of nearly the same hue from infancy until 

 the last time they change their skins, when they are about an inch and a quarter 

 in length. It is commonly with this change of their skins that they lose their yel- 

 low color and become black. When quite young and less than a quarter of 



