52 ANIMAL BIOLOGY 



covers whose principal function it is to cover and protect 

 the abdomen and the membranous second pair of wings 

 which are the true organs of flight. Some of the most 

 common and widely distributed of the Coleoptera are the 

 June-bugs or May-beetles which often come buzzing in 

 through the open windows of lighted rooms in the summer 

 time. The larvae are fat, whitish grubs which live upon 

 the roots of grass and other plants, and frequently do con- 



PiG. 42. Life history of the Colorado potato beetle, a, eggs; b, 

 larva; c, pupa; d, adult insect; e, wing case; /, leg. 



siderable damage. After spending two or three years in 

 the ground they pass through a relatively short pupa stage 

 before emerging. There are many different species which 

 are similar in form and habits. 



The Colorado potato beetle is one of our most serious 

 insect pests. Its original home was in the regions lying 

 near the eastern slope of the Rocky Mountains and, as 

 the cultivation of land extended from the east and the 

 potato gradually traveled westward, the Colorado beetle 

 found in this vegetable an acceptable food plant similar 



