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ing, the front wings are held out to the side of the body like wings of 

 an airplane while the membranous pair provide the power. When 

 beetles are not flying, the front wings meet in a line down the back and 

 the membranous hind pair is so perfectly hidden that it is often thought 

 that beetles do not have wings. The metamorphosis is complete, and 

 many of the larvae are called grubs. The mouth parts are for biting. 

 1. Tiger beetles. These are aggressive insects that run down and kill 

 their prey which usually consist of other insects. Their bodies are often 

 of brilliant metallic shades of green or bronze. 



Courtesy General Biological Supply House 



Fig. 17.4. An earwig. The old superstition that this insect would crawl into the 

 ears of sleeping persons is false, but the name is retained. 



2. Ground beetles. These are small black or brown beetles that have 

 flattened bodies which enable them to crawl under logs and stones. 

 They are one of the farmer's greatest friends because they destroy many 

 insects that are harmful. 



3. Whirligig beetles. Small compact black beetles that whirl around 

 in circles on the surface of the water and catch any insects that happen 

 to fall in are called "whirligig beetles." They walk on the surface film 

 of the water which has enough resistance to prevent their sinking. 



4. Carrion beetles. These feed on dead animals and are sometimes 

 called burying beetles, because they excavate under the body of a dead 



