PROBLEM 8 33 



Problem 8 : A field trip. 



Materials. — For collecting purposes an insect net, cigar boxes 

 containing sheets of cork, insect pins, and a cyanide bottle are 

 useful. (Caution. Do not smell the cyanide ; even the fumes are 

 deadly poison.) See Comstock's Insect Life for good directions 

 how to make nets, cyanide bottle, and collecting boxes. 



NOTE. — Read these directions carefully before beginning work. 

 Object of trip : The object of this trip is threefold : 



1. To find out some of the relations of mutual help existing between plants and 

 animals. 



2. To learn to know a few common insects, and to collect them for later study. 



3. To have such an enjoyable time that you will wish to go again by yourself. 



a. Insects and Flowers 



Method and Observations. — Your trip should include fields and 

 waste lots, covered with weeds and trees. Look for six-legged 

 animals (insects) on plants. Do they receive any protection 

 from such plants? Shelter? Food? Give examples under 

 each of the above headings. Do you find any insects laying their 

 eggs upon plants ? Why do you think they do this ? 



Follow a bee until it alights on a flower. Try to find out exactly 

 what it gets from the flower, and how it does it. Now observe 

 where it goes next. Do bees visit flowers of the same kind in 

 succession ? 



What are your conclusions regarding the mutual relations be- 

 tween the bee and the flower ? Do both receive benefit ? Write 

 your answer on paper supplied by your instructor. 



Look for other flying insects that are on flowers. Extra credit 

 is given for the working out of the relation between a butterfly 

 and a flower. 



Carefully observe the goldenrod blossoms for yellow and black 

 beetles (locust borer) about 1 inch long. Does the beetle get any 

 good from the plant ? Might it give the plant anything in return ? 

 Write a paragraph on this. 



Observe grasshoppers or other insects on stalks of grass. What 

 are they doing there? Do they give any return to the plant? 

 Write a paragraph on this relation. 



HUNTER LAB. PROB. — 3 



