WHEEL-BEARERS 255. 



CHAPTER XIV 



WHEEL-BEAKERS 



I MUST now introduce you to a class of animals pe- 

 culiarly microscopic, since without our marvel -show- 

 ing instrument they are wholly beyond the sphere of 

 human cognizance. Yet they have been ever since its 

 invention favorite objects with the microscopist; and I 

 am free to confess that, among all the classes of ani- 

 mated beings, this of the Rotifer a, has been my own 

 special delight. Their numerous and varied forms, often 

 of remarkable symmetry and elegance, their swiftly-re- 

 volving wheels, their vigorous and sprightly motions, 

 their curious habits and instincts, their complex organ- 

 ization, and the ease and correctness with which this is 

 discerned through their tissues, which have the transpar- 

 ent brilliance of the purest crystal all combine to im- 

 part a charm to the Wheel-bearers, which makes the ob- 

 server hail their appearance in his drops of water with 

 pleasure, and linger over them with unwearied delight. 

 The peculiarity which specially characterizes them is 

 the presence of certain organs called cilia, and their ar- 

 rangement in such a manner that their motion gives to 

 the observer the impression that two toothed wheels are 

 placed on the front of the animal, which are in rapid 

 revolution on their axes. This was believed to be the 

 real fact by the earlier microscopists, though they were 



