48 THE MICROSCOPE. 



man's head and hand have long in vain sought 

 to discover the perpetual motion. For these 

 strange filaments, like our glohe itself, never 

 cease to revolve : whether it be day or night, 

 light or darkness, the cilia exhibit the same 

 circling movements, which seem to cease only 

 with life. Do these movements indicate consci- 

 ousness ? The question has perhaps not yet been 

 fully answered. Dr. Carpenter, though favour- 

 ing the negative, speaks doubtfully. 1 Professor 

 Owen's remarks on the subject are especially 

 worthy of consideration : " If you watch the mo- 

 tions of the Polygastric infusoria, you will per- 

 ceive that they avoid obstacles to their progress ; 

 rarely jostle one another ; yet it is difficult to detect 

 any definite cause or object of their movements. 

 The motions of the Polygastrica have appeared 

 to me, long watching them for indications of 

 volition, to be in general of the nature of re- 

 spiratory acts, rather than attempts to obtain 

 food, or avoid danger. Very seldom can they 

 be construed as voluntary, but seem rather to be 

 automatic, governed by the influence of stimuli 

 within or without the body, not felt but reflect- 



1 Carpenter on the Microscope, pp. 476, 478. 



