i6 A GUIDE FOR THE STUDY OF ANIMALS 



Observations. 



1. Describe the size, appearance, and colors of the plant 

 lice in your collection and their relation to the host plant. 



2. Are the lice active or sluggish ? (Compare with a 

 house fly, for instance.) What proportion of them have 

 wings ? What is the usual method of locomotion .-' 



3. Examining a single winged specimen, how many 

 wings do you find .-' How do they fold .'' What is the 

 character of the wings .' 



4. What is the food of the plant lice.? How is the 

 food obtained } (With a hand* lens identify the piercing 

 organ.) On what parts of the plants are they found.' 

 Does the plant show any indication of being harmed by 

 the lice 1 If so, how 1 



5. Make a count of the plant lice upon a portion of 

 a plant and estimate the whole number upon a plant. 

 Why are plant lice a very serious pest .? 



6. If any plant lice have ants associated with them, 

 study the behavior of the ants in this curious relationship. 

 What advantages result from this relationship of ant 

 and aphis to either or both insects .-• 



Materials. Scale Bugs 



Twigs of trees, leaves, fruit, ferns, etc., infested with 

 these bugs. If possible, have samples of San Jos6 scales, 

 maple scales, and oyster scales. 



Observations. 



1. What is the general size and appearance of the 

 various scale bugs in your collection ? How do they 

 differ in form and size and color ? 



2. Remove a scale and study it carefully with a lens. 

 What is under the scale .' Of what is the scale composed ? 



