62 HOW ARE ANIMALS AND PLANTS DEPENDENT? 



Self-Testing Exercise 



Everywhere in nature we find (1) (2) on plants or 



using them for (3) . Insects also are seen to visit (4) . 



(5) are the most numerous of all (6). An insect has 



(7) body parts ; (8) pairs of legs ; an exoskeleton 



composed of (9) and breathes through (10). The 



eyes are (11). The parts of the insect's body are called the 



(12), (13), and (14). Bugs have mouth 



parts fitted for (15) and (16). Beetles have 



(17) pairs of wings, the outer acting as a (18) for the delicate 



inner pair. Grasshoppers (19) their food. Some of man's 



worst enemies are members of the order (20) . Bees and wasps 



are able to (21). 



PROBLEM II. TO KNOW SOMETHING OF THE STRUCTURE 

 AND LIFE HISTORY OF THE GRASSHOPPER 



Laboratory Exercise. Use living red-legged grasshoppers if possible. 

 Find the three parts : head, thorax, and abdomen. Is there an exo- 

 skeleton ? 



Find the three segments in the thorax? They are called from 

 anterior to posterior, prothorax, mesothorax, and metathorax. Which 

 bear legs? Which bear wings? The membrane-like wings, out- 

 growths of the body, lie straight along the back when at rest. 



Study the hind leg carefully. Compare it with the diagram. Can 

 you find all these parts? Move the leg. How is it used? Can 



Mead.. t , _thort»c 



abdomen. 



cmlzrma — 

 simple eye 

 Compound «^e 



jggtf lay. 



er* 



Identify these parts in your specimen. 



you find any adaptations? How are the wings placed when not in 

 use? When flying? Are there any differences in the two pairs of 

 wings ? - Into how many segments is the abdomen divided ? Are all 



