LOCUST 187 



"What uses have the first pair of wings, or the 

 " wing covers " ? The wings ? How does their 

 structure fit them for their use? For what pur- 

 pose are the veins in the wings ? How are the 

 wings folded ? Unfolded ? "What is the use of 

 the first pair of legs ? Second pair ? Third pair ? 

 Of the spines on the tibia of the third pair ? Of 

 the projections of the femur at the side of the 

 joint between the femur and tibia? Of the hooks 

 and pads ? "What is the position of the wings 

 and legs when the insect is at rest ? "When pre- 

 paring to leap? "When flying ? "When feeding 

 on a blade of grass ? "Why do the joints of the 

 various legs bend in so many different directions ? 

 Compare with the lobster. "Why are the wing- 

 muscles so large? 



d. The abdomen. — "Why is it segmented ? Of what mo- 

 tions is it capable ? Why is there a membrane 

 between adjacent segments? Hold a living lo- 

 cust in the fingers and study its mode of breath- 

 ing. Give reasons for the structure of a single 

 segment. "What is the use of the spiracles ? 

 "Why are there so many? Can a locust be 

 drowned by holding its head under water ? How 

 does the insect "sing"? What is the use of the 

 air-sacs ? Why are there no external ears ? Why 

 should not the ears be on the head ? How does 

 the shape of the ovipositor fit it for its use? 

 What reasons can you give for the presence of 

 such a complicated digestive system? Do you 

 find that it contains much or httle food? Exam- 

 ine some of the contents under a microscope. Of 

 what does the food consist ? 



