Pond Life 
of the water, making little darts and 
then stopping to let the current take it 
down-stream, and then making another 
run to regain its lost ground, or rather 
water. 
Crawling on the bottom, and on the 
stalks and leaves of the water-plants, are 
moving tubes covered with small stones, 
bits of stick, and small shells. Inside 
each of these: curious tubes is a whitish 
grub, a caddis-worm, which when at 
rest withdraws itself altogether inside 
the tube, but can stick out its head and 
legs and walk about when it requires 
exercise or food.’ ‘It turns intomes 
chrysalis inside this cleverly constructed 
shelter, and finally becomes a_two- 
winged fly. The small shells with 
which its dwelling is adorned are very 
often alive, or rather contain the living 
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