THE FLOWER 241 



these allurements to attract the visits of insects. Besides 

 being wasteful, wind pollination is very uncertain. The 

 pollen cannot be blown about very well unless it is dry, and 

 in rainy weather it may all be rotted or washed away before 

 it can reach the stigmas that are ready to receive it. 



Practical Questions 



1. Why do the flowers of oak, willow, and other wind-fertilized plants 

 generally appear before the leaves? (274.) 



2. Can you account for the showers of "sulphur" sometimes reported 

 in the newspapers ? (275.) 



3. Do you see any connection between the feathery stigmas of most 

 grasses and their mode of pollination? (274.) 



4. Why are house plants not apt to seed so well as those left in the 

 open? (Exp. 80.) 



5. Why are the tassels of corn placed at the tip of the stalk? (274.) 



6. Can you trace any connection between the winds and the corn crop ? 

 (274.) 



7. If March winds should cease to l)low, would vegetation be affected 

 in any way? (274.) 



8. Why are wind-fertilized plants generally trees or tall herbs ? (274.) 



9. Is it good husbandry to plant different varieties of corn or other 

 grain in the same field, if :* is desired to keep the strain pure ? (255, 274.) 



10. Is water a good pollen carrier ? (275.) 



11. What is the only class of plants it is likely to reach? 



12. What is the only other agency, besides wind and water, by which 

 this office can be performed ? 



C. Insect Pollination 



M.\TERiAL. — Half a dozen panes of glass, about 6X9; squares of 

 bright-colored cloth or paper; a few spoonfuls of honey or sirup; per- 

 fumes of various kinds, preferably flower extracts ; fetid and disagreeable 

 smelling substances, such as a bit of decaying animal or vegetable matter. 

 Observations on living plants can best be made out of doors or in a green- 

 house, as opportunity offers. 



Experiment 81. Has the color of flowers any attraction for 

 INSECTS ? — Place half a dozen panes of ordinary window glass out of doors 

 or in an open window to which insects can have free access. Lay under 

 the first pane a piece of black paper or cloth, and under the otlu^vs bright- 

 colored pieces of red, blue, white, yellow, and purple. Drop on the center 

 of each pane a little honey or sirup, and watch. Do in.sects show any 

 color preferences? Which color attracts fewest visitors? Which most? 



