50 ARTHROPODS 



different divisions of the thorax. What is the shape of the 

 prothorax ? 



Note the numbers and places of attachment of the legs. 

 Are all the segments of the legs present? How many seg- 

 ments in the tarsus? How is the leg used? 



(2) Between the middle pair of legs and the wings find 

 on each side a small rough surface almost round. Look 

 near it for a small opening, the osteole. From this osteole 

 exudes the offensive odor common to the squash bug. 

 When the fluid leaves the body it evaporates on the granu- 

 lar space. Can this specialization be of any benefit to the 

 animal ? 



(3) How many wings? Lift up an outer one and study 

 its texture, shape and the way it lies on the body. Con- 

 trast the position of the outer wings when at rest with those 

 of the grasshopper. These outer wings are referred to as 

 half wings, can you tell why? Observe the inner wings, 

 What are their size, color and texture? 



(4) With a needle pull one outer and one inner wing 

 out at right angles to the body and draw the dorsal view 

 of the body (X2). In this drawing locate the eyes, an- 

 tennae, and the base of the beak. 



The Abdomen. — Count the number of segments on both 

 dorsal and ventral sides. Do you find spiracles? Where 

 and how many? Draw ventral side, showing osteole and 

 beak (X2). 



Pevelopment. — (i) How does the young squash bug 

 compare with the old one in appearance? 



Is the metamorphosis complete or incomplete ? . Get a 

 number of specimens and raise them to maturity. Draw 

 them in various stages. 



