96 LABORATORY PRACTICE CHAP, xxil 



(b) What proportion of the flowers do you find 

 yellow? blue? red? white? Do these vary 

 during the seasons? 



(f) Observe the flower clusters of the Lantana, and 

 of the Clovers, and notice the change of color, 

 as well as position, during the blossoming and 

 withering. Sketch and describe them. What 

 are the reasons for these occurrences? 



(d} Observe flowers whose petals are variegated 

 with stripes of color or ridges. Where do 

 these lead to, and of what use are they? 



2. Odor. 



(a) With what colors (white, yellow, blue, or red), 

 which you can study, are odors mostly associ- 

 ated? 



(6) Observe that while the odors of most flowers are 

 agreeable to most of us, some flowers have 

 very disagreeable odors : such are the Purple 

 Trillium (T.erectuni) and the Carrion Flower 

 (Smilax herbacea). Such odors attract flies 

 and carrion beetles. 



3. Nectar. 



(a) Examine the Columbine, Pansy, Larkspur, vari- 

 ous Orchids, etc., to see where the nectar is 

 stored ; notice that in these cases the honey 

 is out of the reach of insects with short pro- 

 bosces, and can be obtained only by insects with 

 the longer probosces and by humming-birds. 



() Examine a Buttercup, and notice the small, 

 deeply colored scales at the base of each 

 petal, under each of which is a pit contain- 

 ing honey. What sort of an insect could util- 

 ize this honey? 



