REPRODUCTION 23 



means so that a portion becomes de- 

 tached. The protoplasmic membrane 

 at the sm'face of the cell (which has been 

 mentioned above) is broken by the act 

 of detachment but it is at once repaired 

 in both parts of the cell so that each por- 

 tion is able to continue its growth. 



This may also happen in the artificial 

 cell described above. Here also the mem- 

 brane is instantly repaired when the cell 

 is ruptured and both portions continue 

 to grow. The rupture and repair of the 

 membrane, therefore, do not serve to 

 distinguish the living from the non- 

 living. 



The rupture of the living cell, as pre- 

 viously described, produces two portions 

 which are similar except in size and each 

 constitutes a complete individual. An 

 analogous case (in respect to individual 

 completeness) is found in the strawberry 

 plant, which produces runners. If one 

 of these rimners becomes detached by 

 mechanical means, or by the decay of 

 the connection between it and the mother 



