ANIMAL LIFE IN PONDS & STREAMS 



animal food is partaken of, a different method is 

 pursued by the sun animalcule. A water-flea, for 

 instance, coming into contact with one of the rods 

 will struggle violently in its efforts to escape. Then 

 the sun animalcule shows real signs of life, for some 

 of the other rods bend over and hold the captive 

 so that it, eventually, is passed to a vacuole. 



In our chapter on agriculture we mention a pecu- 

 liar flat worm known as the liver fluke. This un- 

 pleasant creature has one or two relatives who make 

 their home in ponds and, though they are not 

 more beautiful than the liver fluke to look upon, 

 they are quite harmless. One of these flat worms 

 is about f-inch long and not unlike an Indian club 

 in shape. It moves about, with some speed either 

 by the aid of a sucker on its head or by a curious 

 gliding movement. The other pond-frequenting 

 flat worm is more like the liver fluke, its leaflike oval 

 body, about J-inch long, is pointed fore and aft. 

 It is a common sight to see it gliding here and there 

 in search of still smaller animals off which it may 

 make a meal. 



The sea mat and bird's head, two common animal 

 colonies of the sea-shore, possess pond-dwelling 

 relatives of the greatest interest to the microscopist. 

 Like the seaside forms they dwell in colonies. One 

 of the commonest is known as Lophopus Crystallinus 

 and it may be found attached to duckweed, the 

 curious little plant whose tiny leaves float upon the 

 surface of the water. Lophopus, when at rest, re- 

 sembles a little piece of jelly. If we are patient 



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