THE TWENTY-TWO ANCESTRAL STAGES. 43 



If we would now undertake the difficult attempt to dis- 

 ctrvei the phylogenetic course of evolution of these twenty- 

 two human ancestral stages from the very commencement of 

 life, and if we venture to lift the dark veil which covers the 

 oldest secrets of the organic history of the earth, we must 

 undoubtedly seek the first beginning of life among those 

 wonderful living beings which, under the name of Monera, wc 

 have already frequently pointed out as the simplest known 

 organisms. They are, at the same time, the simplest 

 conceivable organisms; for their entire body, in its fully 

 developed and freely moving condition, consists merely 

 of a small piece of structureless primitive slime or plasson, 

 of a small fragment of that extraordinarily important nitro- 

 genous carbon compound, which is now universally esteemed 

 the most important material substratum of all the active 

 phenomena of life. The experiences of the last ten years 

 particularly have convinced us with more and more cer- 

 tainty that wherever a natural body exhibits the active 

 phenomena of life, nutrition, propagation, spontaneous 

 movement, and sensation, a nitrogenous carbon compound, 

 belonging to the chemical group of albuminous bodies, is 

 always active, and represents the material substance through 

 which these vital activities are effected. Whether, in a 

 monistic sense, we conceive the function as the direct effect 

 of the formed material substance, or, in a dualistic sense, we 

 legard " Matter and Force " as distinct, it is at least certain 

 that, hitherto, no living organism has been observed in which 

 the exercise of vital activities was not inseparably connected 

 with a plasson-body. In the Monera, the simplest con- 

 ceivable organisms, the whole body consists merely of plasson, 

 corresponding to the " primitive slime " of earlier natural 

 philosophy. 



