5 50 Handbook of Nature-Study 



Observations i. Where is the pondweed found? Does it ever 

 grow out of water? Does it ever grow in very deep water? Does it ever 

 grow in swiftly flowing water? 



2. Has the pondweed a root? Does the pondweed need to have 

 water carried to its leaves, as it would if it were living in the air ? What is 

 -~ne of the chief uses of the roots to the pondweed.'' Break off a plant, 

 does it float? Do you think it would float off and die, if it was not 

 anchored by its root? 



3. Compare the stern of pondweed with that of any land plant stand- 

 ing straight. What is the chief difference ? Why does the pondweed not 

 need a stiff stem to hold it up? Cut the stem across, and see if you can 

 observe why it floats ? 



4. Examine the leaves. Are all of them below the surface of the 

 water? If some float, how do they differ in texture and form from those 

 submerged? How are they arranged on the stem? Are they set close 

 together? What is the difference in texture between its leaves and those 

 of the jewelweed, dock or any other land plant? If any leaves project 

 out of the water are they different in form and texture from those sub- 

 merged? Sketch the leaf, showing its shape, its edges, and the way it 

 joins the stem. 



5. How far below the surface of the water does the pondweed usually 

 lie ? Does it ever rise up to the water's surface ? When ? Have you ever 

 noticed the pondweed in blossom? How does the blossom look on the 

 water? Can you see the white pollen floating on the surface of the water? 

 Look down into the water and see the way the pondweed stands in order 

 to float its blossoms. 



6. Study the blossom. Note the stem that bears it. Is the part that 

 bears the flower enlarged and stiffer than the stem below? Do you think 

 that this enlarged part of the stem acts like the bob on a fish-line? Ex- 

 amine a flower cluster with a lens. How many flowers upon it? Study 

 one flower carefully. Describe the four stigmas at the center. Describe 

 the anthers arranged around them. Describe the sepal which protects 

 each anther. When the anthers open do they discharge the pollen toward 

 or away from the stigmas ? 



7. What happens after the flowers are pollenated? Do they still 

 float? What sort of seed-capsule has the pondweed? Do the seeds 

 break away and floa 



"Again the wild cow-lily floats 

 Her golden-freighted, tented boats, 



In thy cool caves of softened gloom, 

 Overshadowed by the whispering reed, 

 And purple plumes of pickerel weed, 



And meadow-sweet in tangled bloom. 



''The startled minnows dart in flocks, 

 Beneath thy glimmering amber rocks, 



If but a zephyr stirs the brake; 

 The silent swallow swoops, a flash 

 Of light, and leaves with dainty plash, 

 A ring of ripples in her wake." 



-"Birch Stream", ANNA BOYNTON AVERILL. 



