Suggestions for Laboratory and Field Work to Precede 

 Chapter Sixteen 



1. Examine and make diagrams of several tjrpes of flower 

 clusters, such as spike, catkin, umbel, raceme, and panicle. 



2. Draw several flowers of different types. Label pistil, 

 stamen, corolla, calyx, petal, sepal, receptacle, peduncle, anther, 

 filament, ovulary, style, and stigma. Note differences between 

 monocot and dicot flowers. 



3. >Examine pollen under a microscope, and germinate grains 

 in sugar solutions. Try various strengths from 5- to 10 per cent. 

 Place pollen in a drop of the solution on a micro slide, cover with 

 cover glass, and keep in a moist chamber. The pollen tubes develop 

 by the following day. 



4. Examine the stigmas of flowers for pollen that has ger- 

 minated. 



5. Soak different kinds of seeds in water and study them, 

 noting embryo, endosperm, seed coats, cotyledons, hypocotyl, and 

 plumule. 



6. Study mature pine cones with seeds in place, noting the 

 number of the seeds and their relation to the scales. Dissect a 

 seed and note the seed coats, endosperm, and embryo. 



7. Germinate some seeds and follow the stages in germination. 



8. Collect as many kinds of fruits as possible. Study them 

 from the standpoint of their contents, their origin from the flower, 

 and their methods of dispersal. Draw as many as convenient. 



9. Field trip to study the variety of flowers and flower clusters. 



10. Methods of pollination may best be studied in the field. 

 Note the kinds of insects that visit a particular kind of flower. 

 Compare these insects with those that visit another kind of flower. 

 Is there a noticeable difference in the forms of the two flowers? 

 in the location of the pollen? in the location of the nectar? Does 

 this account for the difference in the kinds of insect visitors ? 



11. Examine several varieties of flowers and note whether or 

 not the stamens shed their pollen when the stigma is ripe, before it 

 is ripe, or after. Does the relative time at which the stigma and 

 pollen mature javor self-pollination, insure it, make it difficult, or 

 prevent it? 



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