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have a very simple embryological basis. Hitherto this could not be 

 recognised; because of the erroneous and impossible character of 

 current embryological views of the course of the life- cycle from gene- 

 ration to generation. The unravelling of the true life-cycle has 

 occupied the author's free working hours during the last fourteen 

 years, and his researches have at length revealed the baseless and 

 impossible nature of three of the fundamental tenets of modern 

 embryology, viz., somatic origin of the germ-cells, direct development, 

 and epigenesis. These three dogmas may be illustrated by the old 

 riddle, of which is there first, the hen or the egg. Under the idea 

 of a somatic origin of germ-cells (which is now emphatically rejected 

 by some of the leading investigators, including Waldeyer), the hen 

 produces from the tissues of her body new eggs — one of the most 

 absurd notions, which ever formed part of any science. Under this 

 view, and under that of direct development, it is the task of the egg 

 from all the parts formed by its cleavage to form a new hen — 

 a thing, which never has happened, and never can occur — and since 

 1759 by epigenesis has been understood the gradual building-up, for 

 instance, of a new hen from all the cleavage products of the egg, 

 exactly as a house is erected from a pile of bricks and other material. 



If the germ-cells do not arise from the soma, direct 

 development and epigenesis become untenable doc- 

 trines! 



The continuity of germ- cells from generation to generation is now 

 becoming generally accepted by embryologists, and, as it can easily be 

 proved, that these do not arise at the first division of the fertilised 

 egg (contra Waldeyer and M. v. Lenhossek), but at a later and 

 very definite period, there must always be, and there are, a number 

 of the cleavage products, concerned neither in the formation of an 

 embryo, nor of germ-cells. These products give rise to an asexual 

 foundation or larva, the phorozoon, upon which the germ-cells, and 

 with these an embryo, take their origin. In human development this 

 foundation, the chorion or trophoblast, is always present, before an 

 embryo appears. Sometimes, indeed, the chorion arises, but no embryo 

 ever forms within it. The formation of an embryo is a mere 

 incident in the life-cycle. It is never the task of the fertilised 

 egg to give rise directly to an embryo, but rather to a set of germ- 

 cells, each and every one of which is endowed with the potentialities 

 of developing and unfolding as an embryo. If two primary germ-cells 

 undergo normal development, the result is the production of identical 

 twins. If in the human subject two such germ-cells develop either 



