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INSECTS. 



Make an enlarged drawing of both wings of one side, 

 naming all these parts on the drawing. 



Development. In almost any cabbage patch during 

 summer and autumn this insect may be found in all 

 stages of development. Collect and observe : 



1. Eggs. These will be found attached singly, usually 

 to the lower surfaces of cabbage leaves. They are quite 

 minute, and are pale yellowish in color. 

 They should be taken with the leaves 

 to which they are attached, and not 

 removed from the leaves until they 

 are to be studied. 



2. Larvce. These are found most 

 abundantly on the fresh but slightly 

 expanded leaves and on both surfaces. 

 Some will be found feeding, others 

 resting. All sizes will be found com- 

 mingled. 



Lift one that is resting, from the 

 leaf, to observe the layer of silk in 

 which its feet are entangled. This silk is spun from a 

 spinneret (modified labrum) below the mouth. A small 

 larva may sometimes be seen actively, and even somewhat 

 violently, swinging its head from side to side as it lays 

 down this layer of silk, thread by thread. 



Watch a large larva that is feeding, to see how methodi- 

 cal is its habit. 



How does a larva walk? Can it walk more easily on 

 the side, or on the margin, of a leaf ? 



Observe the nature and extent of the injury done to 

 the cabbages by these larvae. 



Observe later their hours of feeding. 

 Observe whether they are found in the same positions 

 on sunshiny as on cloudy days. 



LARVA AND PUPA OF 

 CABBAGB BUTTER- 

 FLY (from Riley). 



