PLANARIA FELINA. 75 



each had acquired a longer neck; the body- 

 was taper and well-defined, pursuing a 

 smooth and gliding progression, like that 

 of a planaria which had never suffered mu- 

 tilation. 



Hitherto the source of generation has 

 been veiled in impenetrable mystery. The 

 universe changes its tenants in endless suc- 

 cession : scarce is the parent mature, when 

 it is supplanted by its offspring, and still 

 the origin of both is lost in obscurity. No 

 lucid reasoning aids the philosopher; no de- 

 licacy of experiment leads to conviction. 

 Nature seems to have willed, that the means 

 by which animation is excited, preserved, 

 and transmitted, shall not be disclosed. But 

 is it wonderful, that the vigorous industry 

 of the human mind should have been so 

 unsuccessful here ? Let us remember that 

 the most ordinary incidents, those of con- 

 stant recurrence, and which are ever pa- 

 tent to view, remain unexplained, or that 

 an ill-judged anxiety has substituted con- 

 jecture for truth. 



