SUMMARY 



85 



parts alone, but in some the front legs are used for seizing 

 and holding the food, and in others the legs are used for 

 transporting food. Usually the food is devoured where it 

 is found, but in some cases it is stored, and occasionally it 

 is stored for the young only. 



(3) Climate. — The rigors of the climate form a seri- 

 ous check to the success of insects, and to meet it they adopt 

 the method best suited to their structure. The number of 

 spiracles and the great air capacity of insects render it 

 impossible for them to lead a normal life in cold weather. 

 Therefore the problem with which they have to contend is 

 how to maintain life when food -is exhausted and when the 

 temperature is too low for muscular activity. 



All, or nearly all of the insects that live over winter in the 

 adult state are for a greater or less length of time in a dor- 

 mant state, i. e., a state in which they eat nothing, and 

 breathing as well as circulation of blood is almost stopped. 

 This is called hibernation, and the animal is said to hibernate. 



In addition to hibernation some of them build houses, 

 and store food for use when food is scarce, others go deep 

 into the ground on the approach of winter, others seek pro- 

 tection in decayed logs and under bark, others in straw or 

 corn husks, while others scarcely attempting to seek .protec- 

 tion select any place partially hidden from view, and remain 

 all winter or until they are frozen. 



Many of the insects that do not hibernate as adults spend 

 the winter in the pupa state, while others remain in the 

 egg. The eggs and the pupse are usually protected against 

 inclement weather by being in the earth, in sheltered places 

 or by having thick, warm cocoons. The placing of the 

 eggs and weaving of the cocoons are accomplished by spe- 



