STUDIES OF INSECTS 



37 



G^ Wings membranous, usually folded, few nerves; 



mouth parts, a beak for sucking and piercing Hemiptera 



H^ Outspread membranous 'wings, nearly equal in 



size; antenna very short ZMd.'\-acoxis^\z^oy^ Odonata 



H^ As in P, but antenna not short; wings sometimes 



folded Neuroptera 



H' Both pairs of wings membranous, folded above 

 the back ; fore wings much larger than hind 

 wings; ovipositors long; mouth parts rudi- 

 mentary Ephemerida 



P Fore wings folded over hind wings, crossing at 

 their tips, which are membranous, base of 

 wings thickened, mouth parts a beak for 

 piercing Hemiptera 



F Fore wings leathery, folding either at side of body 

 or on the back; mouth parts for biting, legs 

 often adapted iox jumping Orthoptera 



Note I. — When wings are folded, it will be helpful to remember that 

 thickened fore or cover wings always have membranous wings folded beneath 

 them. 



Insects with no wings Order 



a. Body long and slender, stick-like ; legs for walking. 



Walking stick Orthoptera 



b. Grasshopper-like. Cricket grasshopper .... Orthoptera 



c. Small size ; regions very distinct ; abdomen 



spindle-shape. Ants Hymenoptera 



d. Small size; ant-like in appearance; pale white. 



White ants Isoptera 



e. Flattened body, small size; no compound eyes. 



Springtails and Hsh moths Thysanura 



10. SUMMARY OF THE STUDIES OF INSECTS 



The Effect of Great Numbers 



I. Take some insect for illustration, as the house fly, 

 mosquito, tussock moth, or aphis, and show how insects 

 increase in numbers with great rapidity. 



