326 



Handbook of Nature-Study 



THE ISABELLA TIGER MOTH OR WOOLLY BEAR 



TcacJicr's Story 



"Broivn and furry, Which may be the chosen spot, 



Caterpillar in a hurry, No toad spy you. 



Take your ivalk Hovering bird of prey pass by yon; 



To the shady leaf or stalk, Spin and die, 



Or ivhat not, To live again a butterfly." 



— Christina Rosetti. 



ANY times during autumn, the children find and bring 

 in the very noticeable caterpillar which they call 

 the "woolly bear." It seems to them a companion 

 of the road and the sunshine; it usually seems in 

 a hurry, and if the children know that it is thus 

 hastening to secure some safe place in which to 

 hide during the season of cold and snow, they are 

 far more interested in its future fate. If the cater- 

 pillar is already curled up for the winter, it will 

 "come to" if warmed in the hand or in the sunshine. 

 The woolly bear is variable in appearance; 

 sometimes there are five of the front segments 

 black, four of the middle reddish brown, and 

 three of the hind segments black. In others 

 there are only four front segments black, six 

 reddish ones, and two that are black at the end 

 of the body; there are still other variations, so that each individual will 

 tell its own story of color. There are really thirteen segments in this 

 caterpillar, not counting the head; but the last two are so joined that 

 probably the children will only count twelve. There are a regular num- 

 ber of tubercles on each side of each segment, and from each of these arises 

 a little rosette of hairs; but the tubercles are packed so closely together, 

 that it is difficult for the children to see how many rosettes there are on 

 each side. While the body of the caterpillar looks as if it were covered 

 with evenly clipped fur, there are usually a few longer hairs on the rear 

 segment. 



There is a pair of true legs on each of the three front segments which 

 form the thorax, and there are four pairs of prolegs. All of the segments 

 behind the front three, belong to the abdomen, and the prolegs are on 

 the 3d, 4th, 5th and 6th abdominal segments; the prop-leg is at the rear 

 end of the body. The true legs of this caterpillar have little claws, and 

 are as shining as if encased in patent leather; but the prolegs and prop- 

 leg are merely prolongations of the sides of the body to assist the insect in 

 holding to the leaf. The yellow spot on either side of the first segment is 

 a spiracle; this is an opening leading into the air tubes within the body, 

 around which the blood flows and is thus purified. There are no spiracles 

 on the second and third segments of the thorax, but eight of the abdominal 

 segments have a spiracle on either side. 



The woolly bear's head is polished black; its antennae are two tiny, 

 yellow projections which can easily be seen with the naked eye. The 

 eyes are too small to be thus seen; because of its minute eyes, the woolly 

 bear cannot see very far and, therefore, it is obliged to feel its way. It 

 does this by stretching out the front end of the body and reaching in every 



