ANIMAL LIFE IN PONDS & STREAMS 



as the slipper animalcule is a parasite of the Hydra, 

 Not quite so common as our last object but still 

 common enough to be mentioned here is the beauti- 

 ful ** bell animalcule." Like the Hydra, this 

 creature, except in its very young stages, remains 

 affixed to a water plant. In shape the ** bell animal- 

 cule " resembles a wineglass on a long delicate stem; 

 round the part corresponding to the rim of the glass, 

 there is a fringe of the hair-like, water-lashing struc- 

 tures with which so many of these lowly creatures 

 are provided, and these structures also surround the 

 entrance to the funnel-shaped mouth. When un- 

 disturbed, the bell animalcule has its slender stalk 

 fully extended and its little threads lash the water 

 vigorously, causing currents, containing food mate- 

 rial, to travel towards its mouth. A sharp tap on 

 the microscope slide will cause the creature to con- 

 tract, the threads cease their lashing and the stalk 

 contracts spirally, so that the body of the animal- 

 cule is drawn close to the object to which it is 

 attached. By degrees the spiral uncoils and the 

 little threads resume their lashing. 



Sometimes, as we examine our bell animalcule, 

 we may be fortunate enough to see it splitting into 

 two parts to form two separate individuals. This 

 curious process should be watched carefully. The 

 upper part of the bell splits first and, by degrees 

 the whole bell divides into two equal parts so that 

 we have a pair of bells on a single stalk. The next 

 stage consists of the formation of a ring of whip-like 

 structures round the base of one of the bells; 



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