EXERCISE 112 



The conditions for development and the conditions for growth are usually but not always the same 

 for a given plant or animal. Part of the life cycle may be passed in the winter and another part in 

 the summer, so that the most favorable temperature may not be the same for growth as for later changes. 



Problem. What is the effect of high temperature on the development of an insect that normally 

 spends parts of its resting stage in the cold ? 



What to use. A number of cocoons or pupae of some common insect, gathered in the fall. 



What to do. Place some of the cocoons in a battery jar in the classroom ; leave others in a jar 

 or box out of doors. Watch from time to time to anticipate an early emergence of the adult. Date 

 the insects as they come out. When the last of the brood has emerged, make comparisons as to size, 

 patterns, etc. 



Record. Describe the results and your conclusions. 



Questions. 1. How can you tell that the inside of the cocoons kept indoors was warmer than in 

 the case of those that remained out of doors ? 



2. Is the difference in temperature between the indoor pupae and the outdoor pupae the same as 

 the difference between the classroom and the out of doors ? How do you know ? 



3. What advantages or disadvantages are indicated by any differences in development that you 

 discovered ? 



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