38 INTERRELATIONS OF PLANTS AND ANIMALS 



Insects can, as we have already learned, distinguish differences 

 in color at some distance ; they can see moving objects, but they 



do not seem to be able 

 to make out form well. 

 To make up for this, 

 they appear to have 

 an 'extremely well- 

 developed sense of 

 smell. Insects can dis- 

 tinguish at a great dis- 

 tance odors which to the 

 human nose are indis- 

 tinguishable. Night- 

 flying insects, espe- 

 cially, find the flowers 

 by the odor rather 

 than by color. 



Mouth Parts of the 

 Bee. The mouth of 

 the bee is adapted to 

 take in the foods we 



have mentioned, and is used for the purposes for which man 

 would use the hands and fingers. The honeybee laps or sucks 

 nectar from flowers, it chews the pollen, and it uses part of the 

 mouth as a trowel in making the honeycomb. The uses of the 

 mouth parts may be made out by watching a bee on a well-opened 

 flower. 



Suggestions for Field Work. In any locality where flowers are abun- 

 dant, try to answer the following questions: How many bees visit the 

 locality in ten minutes ? How many other insects alight on the flowers ? 

 Do bees visit flowers of the same kinds in succession, or fly from one 

 flower on a given plant to another on a plant of a different kind? If the 

 bee lights on a flower cluster, does it visit more than one flower in the 

 same cluster? How does a bee alight? Exactly what does the bee do 

 when it alights? 



Butter and Eggs (Linaria vulgaris). From July to October 

 this very abundant weed may be found especially along roadsides 



The head of a bee. A, antennae or "feelers"; 

 E, compound eye; S, simple eye; M, mouth 

 parts; T, tongue. 



