334 The Morality of Nature 



quite comparable to those found in the geological record. 

 But it becomes evident that these embryologic forms are 

 the results of modified repetitions, one after the other, of 

 those forms which have been evolved in the past by the 

 ancestors of the animal, some of whom have become extinct, 

 and have left no record except in this way. The germ or 

 egg cell of every animal starts as a single cell, constituted 

 just as its primal ancestor was, but with all later ancestry 

 added in its chromatin, and it unfolds its heredity by begin- 

 ning with the first or primitive form and adding the sub- 

 sequent, to become at last an organism like its modern 

 parent. It repeats, in its embryology, the life history of its 

 race, from the time when a one cell organization was all 

 that the race had attained, up to the time when it left the 

 body structure of its immediate parent. When it first 

 divides and becomes a two-celled embryo, it resembles that 

 remote ancestor who was mature as a two-celled creature; 

 and then as a four and eight and sixteen celled embryo it 

 still makes over again what its ancestors were and so on 

 to the end. And when all that is done, it may add a character 

 acquired by itself. To better understand what this means, 

 we may compare some present examples of late evolution, 

 with other early ones. Living fowls (which are chosen 

 for example, because of quick responsiveness to environ- 

 ment and visibility of its effects) resemble their parents and 

 their race inevitably and unchangeably in certain matters 

 which the parents found continuously essential. They have 

 bodies, organs, limbs, heads, brains, etc., all of early evolu- 

 tion and existing according to rules long established. But 

 the forms may be changed in regard to matters not so 



