III. THE INTERRELATIONS OF PLANTS AND 

 ANIMALS 



Problem. — To discover the general interrelations of green 

 plants and animals. 



(a) Plants as homes for insects. 



(b) Plants as food for insects. 



(c) Insects as pollinating agents. 



Laboratory Suggestions 



A field trip. — Object : to collect common insects and study their general 

 characteristics ; to study the food and shelter relations of plants and insects. 

 The pollination of flowers should also be carefully studied so as to give 

 the pupil a general viewpoint as an introduction to the study of biology. 



Laboratory exercise. — Examination of simple insect, identification of 

 parts — drawing. Examination and identification of some orders of 

 insects. 



Laboratory demonstration. — Life history of monarch and some other 

 butterflies or moths. 



Laboratory exercise. — Study of simple flower — emphasis on work of 

 essential organs, drawing. 



Laboratory exercise. — Study of mutual adaptations in a given insect 

 and a given flower, e.g., butter and eggs and bumblebee. 



Demonstration of examples of insect pollination. — Field work if possible. 



To the Teacher. — In a broad way this chapter may be used to show the in- 

 terdependence of organisms. As much of the work as possible should be made to 

 depend upon field trips, as the interest thus gained carries over into the laboratory 

 later. Specifically, emphasis should be placed on the accurate determination of 

 relations existing between a given insect and flower as in cross pollination. For 

 this purpose careful study should be made of some one flower in connection with 

 some one insect that is known to act as a pollinating agent. 



To the city child, trips to the parks and fields are especially helpful because 

 they set right his reaction to the term "environment." For that reason especial 

 emphasis is made in this book, a civic biology, to field trips. The young citizen 

 should see a reason for the inclusion of vast sums in a city budget for the purchase 

 and maintenance of parks. This trip should indirectly give him reasons which 

 later will justify his actions as a taxpayer and a citizen. 



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