70 
LABORATORY EXERCISES 
beetle is known as “ complete metamorphosis.’’ (See Waggoner, 
Fig. 193.) 
III. Compare the beetle with a locust and notice several marked 
differences. What can you tell of the habits of the beetle from the 
study which you have made of its various structures? 
EXERCISE 69 (Supplementary) 
THE SQUASH BUG 
If desired, the box elder bug or some other species of bug may be 
substituted for the squash bug. 
I. The External Structure. Examine the specimen provided 
for you. What are its size, its shape, its color, and its markings? 
1. The Head. What is the shape of the head? What is the 
position of the eyes? Examine and describe the antennae. How 
do the mouth parts differ from those of the locust? Explain fully. 
From this study, determine the nature of this insect’s food — 
whether it is solid or liquid. How is the sucking beak carried when 
not in use? What kind of a poison would you use to kill this in¬ 
sect — one applied to the plant upon which it feeds or one applied 
to the body of the insect? Why? 
2. The Thorax. What is the nature of the legs? The number 
of the wings? Compare the texture of the outer and under wings, 
and the anterior and posterior portions of the outer wings. What 
does their structure suggest with regard to the use of each pair? 
Draw one of each pair of wings. 
3. What is the character of the abdomen? 
II. The Stages of Development. Examine a number of young 
squash bugs. Arrange them in the order of their development. 
Note any differences, especially with regard to their wings. (See 
Waggoner, Fig. 191.) 
