ON TIIK fJENKTIC VIEW OF NATURE. 



349 



sense liy Meckel, mui iUa-i, jukI Series. It h.as some- 

 times been termed von liaer's law, tlmuiih mui IJaer 

 very carefully guarded himst'll' against many ]»o])ular 

 versions of the analogy, appl} iug it only wiihin the 

 limits of the fonr great groups or plans of organisation 

 into which he divided the animal kingdom.^ In his 



zustande der hiilieren Thioro uud 

 dem permaneiiten der niederen 

 stattfindenden Parallele ' (1811): 

 "There i.-* no good phyt^iologist who 

 has not been struck by tlie observa- 

 tion that the original form of all 

 organisms is one and the same, and 

 that out of this one form all, the 

 lowest as well as the highest, are 

 developed in such a manner that 

 the latter pass through tlie per- 

 manent forms of the formei- as 

 transitory stages. Aristotle, Hal- 

 ler, Harvey, Kielmeyer, Autenrieth, 

 and many others, have either made 

 this observation incidentally, or, 

 especially the latter, have drawn 

 particular attention to it, and 

 drawn therefrom results of per- 

 manent importance for physiology'. '" 

 Louis Agassiz, in his celebrated 

 "Essay on Classification" (1859), 

 though rejecting the doctrine of 

 descent, "insisted, nevertheless, on 

 the correspondence between stages 

 in embryonic development and the 

 grades of differentiation expressed 

 in the classification of living and 

 extinct animals " (Thomson, ' The 

 Science of Life,' j). 134). 



^ " A careful examination of von 

 Baer's ' laws ' shows that he did 

 not accept the recapitulation with- 

 out many saving clauses. He be- 

 lieved in it much less than many 

 a modern embryologist, such as F. 

 M. Halfour or A. Milnes Marshall '" 

 (Thomson, j). 133). Before the 

 puljlication of Haeckel's ' Generelle 

 Morphologic ' the naturalist who 

 seems to have most clearly ex- 

 pressed the recapitulation theory 



was Fritz Midler, who in 1864 

 published his famous tract ' P'iir 

 Darwin,' which appeared in 1868 

 in an English translation by Dallas, 

 with the title 'Facts and Argu- 

 ments for Darwin.' The work of 

 Fritz Jlilller, who for many years 

 lived in the Brazils, isolated and 

 secluded, and devoted to scientific 

 observation, was welcomed by Dar- 

 win as one of the first and greatest 

 supports to his doctrine : the 

 author was singled out by him as 

 the "prince of observers," and 

 frequently referred to in the latei- 

 editions of the 'Origin of Species." 

 Delage considers him to have first 

 expressed the fundamental bio- 

 genetic law (' L'Heredite,' pp. ITjO, 

 469), and this is in agj-eement with 

 Haeckel's own declaration in the 

 13tli chapter of the ' Historj' of 

 Cieation.' It is, however, well to 

 mention that the recapitulation 

 theory has found little favour w ith 

 botanists ; that Haeckel himself 

 admits that the parallelism be- 

 tween ontogenesis and phylogenesis 

 is general and not exact ; that there 

 is a tendency to abbreviation ; that 

 recent adaptations (called by him 

 " kainogenetic ') may mask more 

 ancient ("palingenetic '") features, 

 &c. See J. A. Thomson, 'The 

 Science of Life,' p. 13.'). Ziegler, 

 in his recent excellent leview of 

 the ' Present Position of the Doc- 

 trine of De.xcent ' (Jena, 1902, p. 12), 

 admits that the theory of paral- 

 lelism has " perhaps not realised 

 all the expectations " which were 

 cherished thirty years ago. 



