LABORATORY PRACTICE 



5. The Pea Flower is a type of irregular flower found upon 

 the 'majority of the plants of the pea family. It is 

 called a papilionaceous or butterfly flower. 



IV. Study also, if possible, flowers of the Larkspur and 

 the Pansy or Violet for excellent irregular flowers ; notice 

 that one or more of the petals or sepals in each is pro- 

 longed into a tube or spur which contains honey. What is 

 this honey for? Are the stamens all alike? Is the flower 

 insect- or wind-pollinated? What is the numerical plan? 



V. Examine, with the aid of the teacher, the flower of 

 some Orchid, if possible, and notice the great irregularity 

 and the devices for compelling the insect to touch first the 

 stigma, leaving upon it the pollen brought from the last 

 flower visited, and then, upon backing out, to smear itself 

 with the pollen of this flower, to carry to another. 



VI. Unsymmetrical Flowers. Returning to a flower 

 with a papilionaceous corolla, notice : 



1. The calyx how many sepals are there? 



2. The corolla how many petals are there? 



3. The stamens how many are there? 



4. The pistils how many are there ? How many styles ? 



How many stigmas ? How many cells in the ovary ? 

 How many placentae? 



5. What is the numerical plan of this flower ? Write out the 



reasons for your answer. 



VII. Review and distinguish carefully between these varia- 

 tions in structure and fix in mind the significance of each. 



