142 The Science of Life. 



with the gradual emergence of the theories of hered- 

 ity into fuller scientific daylight. It is only necessary 

 to linger for a little over the preformationist 

 thefunijue-* hypotheses to which we have already referred 

 ness of the ( c hap. x.). According to the extreme pre- 



Germ-cells. ). r . '. , T T n ,1 ^i 



formatiomsts, such as Haller, the egg or the 

 male element was supposed to contain an excessively 

 minute micro-organism, a complete though miniature 

 model of the adult. This was supposed to be stimu- 

 lated from potential to actual life by fertilization. By 

 the absorption of nutriment in its interstices it was 

 supposed to unfold, expand, or "evolve" into the adult 

 organism. The " animalculists " found this miniature 

 model in the male element, which was believed to be 

 nourished by the ovum, while the "ovists" held that 

 the model lay in nuce within the egg, and was, so to 

 speak, awakened by the sperm. This hypothesis was 

 further backed up by that of " emboitement" ', according 

 to which the germ was not only itself a marvellous 

 micro-organism, but contained in ever smaller propor- 

 tions, after the manner of an infinite juggler's-box, the 

 miniature models of the generations to follow. But how 

 the germ became endowed with its marvellous supposed 

 organization was left an unsolved riddle. 



It must be allowed that, in their general proposition 

 that the germ was a potential organism, the preforma- 

 tionists were correct. The germ cell does imply the 

 future organism, and future generations of organisms as 

 well. But the preformationists exaggerated this idea 

 into a denial of individual development, and in default 

 of any theory as to the origin of the initial organization 

 of the germ-cell they were forced to fall back on mysti- 

 cal or metaphysical verbalism. The early researches of 

 Wolff alone were quite sufficient to show that neither 

 the extreme theory of preformation nor its consequent 

 hypothesis of emboitement had any basis of fact. For 

 Wolff showed that there is no preformed model, but that 

 there is a visible development of the apparently simple 

 into the obviously complex. Yet as he also was unable 

 to throw any light upon the inevitable question, " How 

 does this apparently simple germ-cell come to have such 



