334 PROGRESS OF SCIENCE IN THE CENTURY. 



peared in post-Darwinian days. To Cuvier, who was 

 an anti-evolutionist, the " correlation of parts " was 

 simply a morphological fact. 



We would place next the name of Goethe, not be- 

 cause of his anatomical discoveries, which were few 

 in number, but because of the clearness with which 

 his genius discerned and proclaimed " the funda- 

 mental idea of all morphology — the unity which 

 underlies the multifarious varieties of organic 

 form/' * 



The idea which was more or less clearly in the 

 mind of Joachim Jung (1678) and of Linna3US 

 (1760, 1763) that the appendicular organs (leaves, 

 bracts, sepals, petals, etc.) arising from the stem of 

 a flowering plant are all fundamentally the same 

 leaf-organ in various forms, was rehabilitated and 

 in part demonstrated by the embryologist Casper 

 Friedrich Wolff (1767), who said "all parts of 

 the plant, except the stem, are modified leaves," and 

 by Goethe in his famous essay Yersuch die Meta- 

 morphose der Pflanzen zu erhldren (1790). It 

 may be that the evidence Goethe gave of the funda- 

 mental unity of foliar and floral organs would not 

 be considered conclusive nowadays, but his essay — 

 published with some difficulty and for many years 

 little noticed — is a famous document in the archives 

 of botany, an early expression of an idea which has 

 now saturated the whole science. The morphological 

 equivalence of the appendicular organs is now uni- 

 versally admitted, though the direction in which the 

 evolution has taken place — ^whether from foliage-leaf 

 to reproductive-leaf (sporophyll) or vice versa — re- 

 mains a subject of discussion. 



Some years previously Goethe had made an- 



♦ Geddes, Article Morphology, Encyclopwdia Britannica. 



