THE PROCESS OF KEPKODUCTION. 1 83 



Every organism, every living individual, owes its exist- 

 ence either to an act of unparental or Spontaneous Genera- 

 tion (Generatio Spontanea Archigonia), or to an act of 

 Parental Generation or Propagation (Generatio Parentalis, 

 Tocogonia), In a future chapter we shall have to consider 

 Spontaneous Generation, or Archigony. At present we must 

 occupy ourselves with Propagation, or Tocogony, a closer 

 examination of which is of the utmost importance for under- 

 standing transmission by inheritance. Most of my readers 

 probably only know those phenomena of Propagation which 

 are seen universally in the higher plants and animals, the 

 processes of Sexual Propagation, or Amphigony. The pro- 

 cesses of Non-sexual Propagation, or Monogony, are much less 

 generally known. Tlie latter, however, are far more suited 

 to throw light upon the nature of transmission by inherit- 

 ance in connection with propagation. 



For this reason, we shall first consider only the phe- 

 nomena of non-sexual or monogonic propagation (Mono- 

 gonia). This appears in a variety of different forms, as for 

 example, self-division, formation of buds, the formation of 

 germ-cells or spores (Gen. Morph. ii. 36-58). It will 

 be most instructive, first, to examine the propagation of 

 the simplest organisms known to us, which we shall have 

 to return to later, when considering the question of 

 spontaneous generation. These very simplest of all 

 organisms yet known, and which, at the same time, are the 

 simplest imaginable organisms, are the Monera living in 

 water ; they are very small living corpuscles, which, strictly 

 speaking, do not at all deserve the name of organism. 

 For the designation " organism," appHed to living creatures, 

 rests upon the idea that every living natural body is com- 



