A MANUAL OF BOTANY 



65 



of the flower and the relation of all its parts, adapt these 

 flowers for such a method. 



Field observation. If possible, examine blooming clover- 

 plants for insect visitors, and observe how they proceed in 

 order to obtain the nectar. Remove the flowers from a fresh 

 red-clover head and draw out the nectar by suction. Com- 

 pare the bees that frequent the red and white clovers. 

 Are they the same kinds ? Recall that the irregular flowers 

 of the orchid were also special contrivances for securing in- 

 sect pollination. What would you infer about irregular 

 flowers in general ? 



Table. Make a table of flowers of the Pea family which 

 you are able to find from any sources, using the following 

 form : — 



Name 



Inkloui 



CENCE 



Flowkk 



(.01,0 It 



F LOWER 



Size 



Where 

 Native 



Use 



Value as soil restorer. The Pea family (Leguminosce is 

 the technical name) is a remarkable one in many ways, but 

 in no way more so than in the peculiar sfpnbiotic relation 

 that all members have with nitrogen-fixing bacteria. (See 

 Bacteria study.) 



If in season, pull or rather dig up a red clover, sweet 

 clover, alfalfa, or white clover; wash all the dirt from the 

 roots and examine the numerous tubercles caused by the 

 bacteria. A chemical test will show a large amount of 

 nitrogen in these swellings. 



Nitrogen is a powerful plant tonic, producing great 

 activity in purely vegetative (growth) work. The soil may 

 obtain this plant food in four ways : — 



