of ancestral germ-plasms Zl 



development, for each corresponds to a single 

 ancestor. But there are many of them, 

 and so a struggle ensues. The card or plasm 

 of one ancestor — a paternal grandmother 

 say — succeeds in shaping the nose : another 

 — perhaps a maternal great-grandfather — 

 provides the mouth, and so on. Though 

 any one of them might conceivably have 

 furnished the whole, it is far more likely 

 that all or most of the pack have a share 

 in it. In all this — the mingling of ancestral 

 plasms, the reducing division, the reversion 

 and atavism — we are, so far, in the region 

 of fact. But when Weismann asks us to 

 regard these ancestral plasms as themselves 

 quite stable, we enter the region of fable. 

 And even in this region, if we try to picture 

 out — not everyday instances of heredity — 

 but the primitive heredity, the link, that is 

 to say, which long ago connected the 



