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THE LIFE OF FLOWERING PLANTS 
In our study of flowering plants we can begin with any 
organ or with any stage in their life history. Many persons 
begin with the seed. In this book we shall begin with the 
flower. 
If the study of plants is begun in the fall, the nasturtium 
flower offers a good example of adaptations. You will 
notice that it has (1) a striking color in contrast with the 
foliage. This enables insects to see it readily. (2) It has 
an odor. This enables insects that are guided largely by 
the sense of smell to find it. (3) It has a long nectar spur 
on one side of the flower. This attracts the larger insects 
for the food they can get. (4) The lower petals have an 
inner fringe which retards the crawling insects that are trying 
to get the nectar. (5) The upper petals project over the 
other parts of the flower. This keeps the rain from running 
down the nectar spur and prevents the pollen from becoming 
wet. (6) The lower petals have stripes that lead to the 
opening of the nectar spur. This indicates the direction 
that insects should travel to find the opening quickly. 
(7) The anthers mature at different times. This insures 
a supply of pollen on different days so that some of the pollen 
is in condition to use, even if some has been spoiled by un¬ 
favorable weather. (8) The anthers and stigma mature 
at different times so that the pollen cannot-get on its own 
stigma. This ensures hardier seeds by preventing inbreed¬ 
ing. There are at least eight ways in which the nasturtium 
flower is adapted to the visits of insects and to the protection 
of its pollen and nectar. There are many other aspects of 
the study of flowers as interesting as the study of adaptation, 
some of which will be mentioned later. 
LABORATORY STUDY OF A NASTURTIUM 
Provide each pupil with a nasturtium flower. 
Draw the flower, and label the parts as follows : (1) sepals, the outer¬ 
most, greenish parts; (2) petals, the colored, larger parts; (3) stamens, 
