52 The Recapitulation Theory and Human Infancy 



ical reference is a general one and not to a series of ancestral 

 forms. 



"This repetition is seldom particular, or detailed, never com- 

 plete, yet so many of the phenomena of development can be 

 satisfactorily interpreted from the historical point of view, seem- 

 ing to have this historical sign rather than an immediately adap- 

 tive relation, that as a general statement the law remains funda- 

 mentally true." 87 



(3) The view that the facts upon which the traditional theory 

 of recapitulation has been based can be better explained as indi- 

 cating resemblances between ontogenies of descendants and 

 ontogenies of ancestors has the support of Hurst, Morgan, 

 Sedgwick, Cunningham, Griggs, and others. Of this view 

 Griggs (1909) has this to say: 



"The form which has the largest number of adherents is per- 

 haps that proposed by Morgan ('03), who believes that animals 

 in their ontogeny repeat not the adult, but the embryonic stages 

 of their ancestors. . . .Much of the evidence which the zoologists 

 bring forward in favor of such a modification as against any 

 broader application is so conclusive, one must acknowledge 

 that such is a correct statement of the facts in the particular 

 cases cited, whatever the general law of development may be .... 



"The evidence presented by the kelps clearly tends to establish 

 the repetition theory of Morgan. " 88 



Griggs does, however, find evidence among the kelps of the 

 retention of adult characters, and concludes with a statement 

 favorable to recapitulation. 



Hurst's application of von Baer's law to the disparagement 

 of recapitulation has been given above. His constructive 

 statement from the same point of view follows: 



"Each transient stage in the development of any individual 

 is a modification of the corresponding stage of development of 

 its ancestors. It is in no case a modification of the adult stage 

 of the ancestor. The adult stage of a bird, and no other, cor- 

 responds to the adult stage of the fish-like ancestors (if it ever 

 had such ancestors.) " 89 



Morgan refers to this suggestion of Hurst with approval. 

 His own treatment of the subject under discussion may be 



" Kellicott, General Embryology, 1913, p. 24. 



ss Kelps and the Recapitulation Theory, Amer. Naturalist, Vol. 43, 1909, p. 97. 



s* Loc. tit., p. 199. 



