90 



HOW ARE ANIMALS AND PLANTS DEPENDENT? 



course of a single trip from the hive, and it is then that cross- 

 pollination takes place. 



Other flower visitors. Other insects besides the bee are pollen- 

 izing agents for flowers. Among the most useful are moths and 

 butterflies. Both of these insects feed only on nectar, which they 

 suck through a long tubelike proboscis. The heads and bodies 

 of these insects are more or less thickly covered with hairs, and 

 the wings are thatched with tiny hairlike scales. All these 

 structures are of some use to the flower because they collect and 

 carry pollen; but the palp, a fluffy structure projecting from 

 each side of the head of a butterfly, collects a large amount of 

 pollen, which is deposited upon the stigmas of other flowers when 

 the butterfly pushes its head down into the flower tube after nectar. 



Flies and a few other insects are agents in cross-pollination. 

 Humming birds are also active in pollinating some flowers. 

 Snails are said in rare instances to carry pollen. Man and animals 

 may pollinate a few flowers in brushing past them through the fields. 



Practical Exercise 12. Devise an experiment to determine if a given in- 

 sect is attracted to a given flower by color or by odor. 



List in a table the plants in your neighborhood that are pollinated by butter- 

 flies, bees, beetles, flies, bugs, or other insects. 



Butterflies 



Bees 



Beetles 



Flies 



Bugs 



Other Insects 















Self-Testing Exercise 



(1) is accomplished by the insect visitors to flowers. The 



chief adaptations in the bee for carrying pollen are the (2) on 



the legs and body. The bee uses pollen for (3) and carries it 



to the hive in (4) (5), concavities on the (6) 



pairoflegs (7), (8), (9),... (10), 



(11), and other animals may aid in cross-pollinating flowers. 



These animals visit flowers for (12) and not to (13) them. 



