INSECT ORDERS 



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each egg separately and puts it on a tall stalk and the first larva to 

 hatch cannot eat its brothers and sisters in their egg cases. They are 

 extremely beneficial because the aphids are one of the most destructive 

 of the plant parasites and some wise gardeners gather the adults with an 

 insect net and release them in their garden. 



Photo by Winchester 



Fig. 17.10. A dobson fly. The long jaws shown are found only in the male and are 



used to embrace the female when mating. The larvae live in water and are called 



hellgrammites. They make excellent fish bait. 



2. Ant lion. The adults of this insect are somewhat larger and more 

 stockily built than the aphis lion adults. Eggs are laid in dry loose dirt 

 and hatch into the familiar ant lion, or doodlebug, that builds a cone- 

 shaped pit in the dirt and waits for an ant, or other insect, to venture 

 over the edge of this trap. When this happens, the insect finds that the 

 harder it struggles to get out the faster it slips to the point of the cone 

 where the jaws of the ant lion are waiting to crush and devour it. 



3. Scorpion flies. These get their name from the fact that the male 

 has claspers at the tip of its abdomen that make it look somewhat like 

 a scorpion, but it has no sting. 



4. Caddis flies. The adults look somewhat like moths with fine hairs 

 on their wings that resemble scales of the moths. The larvae live in 



