40 FLOWERS AND THEIR WORK 



Insects as Pollinating Agents. 1 No one who sees a hive of 

 bees with their wonderful communal life can fail to see that these 

 insects play a great part in the life of the flowers near the hive. 

 A famous observer named Sir John Lubbock tested bees and wasps 

 to see how many trips they made daily from the hive to the flowers, 

 and found that the wasp went out on 116 visits during a working day 

 of 16 hours, while the bee made but a few less visits, and worked 

 only a little less time than the wasp worked. It is evident that 

 in the course of so many trips to the fields a bee must light on and 

 cross-pollinate many hundreds of flowers. 



Study of a Bee. The body of a bee (and of all other insects) 

 is divided into three parts. Attached to the middle part (the 



Bumblebees ; a, queen ; b, worker ; c, drone. 



thorax) are three pairs of jointed legs and two pairs of tiny wings. 

 By the legs and the jointed body we are able to distinguish insects 



1 Suggestions for Field Work. At this point, at least one field trip should be 

 introduced for the purpose of studying under natural conditions the cross-pollina- 

 tion of flowers by insects. For suggestions for such a trip, see Hunter and Valentine, 

 Manual, page 207. Many of the following exercises on fall flowers may profitably 

 be taken in the field and reported on by the pupil as class exercises. Excellent sug- 

 gestions for a field trip may be found in Andrews, Botany All the Year Round. To 

 make such a trip successful, the teacher should first know the locality and should 

 have directions in the hands of each pupil before starting. Flowers which are abun- 

 dant in the fall and which show adaptations easily worked out by pupils are the 

 evening primrose (Onagra biennis), moth mullein (Verbascum blattaria), and jewel 

 weed (Impatiens biflord). 



Directions for work on these forms and for a field trip will be found in the Labo- 

 ratory Manual, Prob. VJJ. 



