314 



THE HISTORY OF CREATION. 



If we examine this parallelism of the three organic 

 series of development more accurately, we have to add 

 the following special qualifications. Ontogeny, or the 

 history of the individual development of every organism 

 (embryology and metamorphology), presents us with a 

 simple unhrancJiing or graduated chain of forms ; and so it 

 is with that portion of phytogeny which comprises the 

 palseontological history of development of the direct ancestors 

 only of an individual organism. But the ivhole of jpliylogeny 

 — which meets us in the natural system of every organic 

 tribe or phylum, and which is concerned with the investi- 

 gation of the palseontological development of all the 

 branches of this tribe — forms a branching or tree-shaped 

 developmental series, a veritable pedigree. If we examine 

 and compare the branches of this pedigree, and place them 

 together according to the degree of their differentiation and 

 perfection, we obtain the tree-shaped, branching, systematic 

 developmental series of comparative anatomy. Strictly 

 speaking, therefore, the latter is parallel to the whole of 

 phylogeny, and consequently is only partially parallel to 

 ontogeny ; for ontogeny itself is parallel only to a portion 

 of phylogeny. 



All the phenomena of organic development above dis- 

 cussed, especially the threefold genealogical parallelism, 

 and the laws of differentiation and progress, which are 

 evident in each of these three series of organic development, 

 and, further, the whole history of rudimentary organs, are 

 exceedingly important proofs of the truth of the Theory of 

 Descent. For by it alone can they be explained, whereas 

 its opponents cannot even offer a shadow of an explanation 

 of them. Without the Doctrine of Filiation, the fact of 



