SOME COMMON INSECTS 15 



with a single pair of flies in April, how many offspring will there be by fall, 

 provided none die ? Where do the flies that appear in the spring come from ? 

 Why is it especially difficult to keep flies out of the house in the fall ? What 

 are some of the best measures to take to exterminate the fly ? 



Make tabulations on the blank pages with the following headings and 

 fill in information regarding the injurious and beneficial insects in so far 

 as you can from your own knowledge or from books easily available in the 

 library. 



1. INJURIOUS INSECTS 



NAME OF INSECT WHAT IT INJURES METHOD OF COMBATING 



2. BENEFICIAL INSECTS 



NAME OF INSECT IN WHAT WAY IT IS BENEFICIAL 



Spiders. Locate a web of the large garden spider and capture an 

 insect like the cricket or grasshopper. Throw it into the web. Observe 

 what the spider does, and especially look to see how it spins the silk in which 

 it wraps its prey. On the blank page opposite make a sketch of the web. 

 What is the advantage of a web ? Do you know of any other animal or 

 plant traps found hereabout ? If you can find a spider spinning its web 

 observe how this is accomplished. Find somewhere about the house a 

 cobweb. Do the strands have any definite arrangement? Find on the 

 grass the web of the funnel weaver. Where does the spider stay in this 

 web ? Look under sticks and stones for wolf spiders. They are swift run- 

 ners and the females will be found carrying the round silken egg case. On 

 the ground and on tree trunks will be found some of the jumping spiders. 

 How do they capture their prey ? Look on the fall asters anjd sunflowers 

 for specimens of the crab spider. Watch on the field trips for the young 

 spiders sailing through the air on the tufts of their silk. 



