144 LIFE A AW DEATH. [III. 



involves the transmission of acquired characters, which is at 

 present unproved and must not be assumed to occur until it 

 has been either directly or indirectly demonstrated \ I cannot 

 imagine any way in which the somatic cells could communicate 

 this assumed death by starvation to the reproductive cells in 

 such a manner that the somatic cells of the resulting offspring 

 would spontaneously die of hunger in the same manner and at 

 a corresponding time as those of the parent. It would be as 

 impossible to imagine a theoretical conception of such trans- 

 mission as of the supposed instance of kittens being born 

 without a tail after the parent's tail had been docked ; although 

 to make the cases parallel the kittens' tails ought to be lost at 

 the same period of life as that at which the parent lost hers. 

 And in my opinion we do not add to the intelligibility of such 

 an idea by assuming the artificial removal of tails through 

 hundreds of generations. Such changes, and indeed all 

 changes, are, as I think, only conceivable and indeed possible 

 when they arise from within, that is, when they arise from 

 changes in the reproductive cells. But I find no difficulty in 

 believing that variations in these cells took place during the 

 transition from Homoplastids to Heteroplastids, variations 

 which formed the material upon which the unceasing process 

 of natural selection could operate, and thus led to the differ- 

 entiation of the previously identical cells of the colonj^ into 

 dissimilar ones — some becoming perishable somatic cells, and 

 others the immortal reproductive cells. 



It is at any rate a delusion to believe that we have explained 

 natural death, by deriving it from the starvation of the soma of 

 the Orthonectides, by the aid of the unproved assumption of 

 the transmission of acquired variations. We must first explain 

 why these organisms produce only a limited number of repro- 

 ductive cells which are all extruded at once, so that the soma is 

 rendered helpless. Why should not the reproductive cells 

 ripen in succession as they do indirectly among the Monoplas- 

 tides, that is to say in a succession of generations, and as they 

 do directly in great numbers among the Metazoa ? There 

 would then be no necessity for the soma to die, for a few 

 reproductive cells would always be present, and render the 

 persistence of the individual possible. In fact, the whole 



^ See the preceding essay ' On Heredity.' 



