THE SPKING FLOBA 175 



d. Pollination. How is pollination secured through the 



agency of visiting insects ? 



e. Drawing. Draw a median long section of the flower 



to show the relation of the floral parts which insure 

 cross-pollination. Label accurately. 



f. Summarize under the following headings the mechanisms 

 of the violet which adapt it for cross-pollination. 



(1) Perianth modifications. 



(2) The relation of the pistil, stigma, and anthers. 



(3) The anther tube and pollen shedding. 



(4) The relation of a visiting insect to the flower in 



securing nectar. 



4. Analysis. Analyze one or more species of violets, record- 

 ing the family, scientific, and common name. 



CRUCIFERAE 



Study the habitat and habit of some of the important 

 members of the cruciferous family. 



1. Habit. 



a. Stem and roots. What are the distinctive features of the 



stems and roots of the Cruciferae that you are study- 

 ing ? Are there characteristics which are unusual ? 

 What is the nature of the juice or sap ? 



b. Leaves. Observe any distinctive characteristics of leaves 



in members of the family under observation. 



2. Reproduction. 



a. Determine the nature of the inflorescence and the 



structure of the flower. 



b. Drawings. Draw a ground plan of a flower of some one 



of the Cruciferae. Draw a median long section of a 

 flower to show the relation of the perianth, stamens, 

 and pistil. 



