Insect Study 



317 



support, pushes ofif the shrunken skin just shed and inserts the hooks, 



with which it is fur- 

 nished, firmly in the 

 button of silk. Some- 

 times during this pro- 

 cess, the chry-salis loses 

 its hold entirely and falls 

 to the ground, which is 

 a fatal disaster. The 

 chrysalis is yellowish 

 brown and usually looks 

 very much like the ob- 

 ject to which it is at- 

 tached, and is thus un- 

 doubtedly protected 

 from sight of possible 

 enemies. Then some 

 day it breaks open, and 

 from it issues a crumpled 

 mass of very damp insect 

 velvet, which soon ex- 

 pands into a beautiful 

 butterfly. 



References . — Every- 

 The chrysalis. The caterpillar of the day Butterflies, Scud- 



Photo by M. V. Slingerland. black swallow-tail ready der; Moths and Butter- 

 to change to a chrysalis. fljeg^ Dickerson ; How to 



Know the Butterflies, Comstock; Moths and Butterflies, Ballard. 



LESSON LXX 



The Black Swallow-Tail Butterfly 



Leading thougJit — The caterpillars of the swallow-tail butterflies have 

 scent organs near the head which they thrust forth when attacked, thus 

 giving off a disagreeable odor which is nauseating to birds. 



Method — In September, bring into the schoolroom and place in the 

 terrarium, or breeding cage, a caraway or parsley plant on which these 

 caterpillars are feeding, giving them fresh food day by day, and allow the 

 pupils to observe them at recess and thus complete the lesson. 



The Caterpillar and Chrysalis. 



Observations. — i. Touch the caterpillar on the head wath a bit of 

 grass. What does it do? What color are the horns? Where do they 

 come from? Are there two separate horns or two branches of one horn? 

 What odor comes from these horns? How does this protect the cater- 

 pillar? Does the caterpillar try to hide under the leaves when feeding? 

 Is this evidence that it is not afraid of birds? 



2. Describe the caterpillar as follows: What is its shape? Is it 

 larger toward the head or the rear end ? What is its ground color? How 

 is it striped ? How many black stripes ? How many yellow spots in each 



