168 THE FLOWER. 



gous with leaves ; that the sepals are comparative!}- little, the 

 petals more, and the reproductive organs much modified from the 

 type, that is from the leaf of vegetation. This is simply what 

 is meant by the proposition that all these organs are transformed 

 or metamorphosed leaves. What would have been leaves, if 

 the development had gone on as a vegetative branch, have in 

 the blossom developed in other forms, adapted to other func- 

 tions. Linnaeus expressed this idea, along with other more 

 speculative conceptions, dimly apprehended, by the phrase Vege- 

 table Metamorphosis. Not long afterwards, this fecund idea 

 of a common type, the leaf, of which the pails of the flower, 

 &c., were regarded as modifications, was more clearly and differ- 

 ently developed by a philosophical physiologist, Caspar Frederic 

 Wolff. Thirty years later, it was again and wholly independ- 

 ently developed by Goethe, in a long-neglected but now well- 

 known essay, on the Metamorphosis of Plants. Twentj'-three 

 years afterwards, similar ideas were again independently pro- 

 pounded by DeCandolle, from a different theoretical point of 

 view ; and finally the investigation of phyllotaxy has completed 

 the evidence of the morphological unity of foliaceous and floral 

 organs. 1 



1 The contribution of Linnaeus is on p. 301 of the Philosophia Botanica, 

 1751 ; and all that is pertinent is in the following propositions : 



Plumulam seminis saepius terminal aut flos aut gemma. 



Principium florum et foliorum idem est. 



Principium gemmarum et foliorum idem est. 



Gemma constat foliorum rudimentis. 



Perianthium sit ex connatis foliorum rudimentis. 



His dissertation, Prolepsis Plantarum, in Amoen. Acad. vi. (1760), added 

 nothing but obscure speculations to the former comparatively clear 

 statements. 



Kaspar Friedrich Wolff's contribution is in his Theoria Generationis, 

 mainly concerning animals, published in 1759, and an enlarged and amended 

 edition in 1774. He first clearly conceives the plant as formed of two ele- 

 ments, stem and leaf, but develops only the morphology of the latter, and 

 under the hypothesis that leaves of vegetation become bud-scales or floral 

 organs, as the case may be, through degenerescence or diminution of vege- 

 tative force, which is renewed in the bud or in the seed. 



Johann Wolfgang GSthe's Versuch die Metamorphose der Pflanzen zu 

 erklaren was published in 1790. in 86 pages. For the translations and 

 reproductions, see Pritzel, Thesaurus. To the French translation by Soret. 

 with German text accompanying (Stuttgart, 1831), and also to that of Ch. 

 Martens (CEuv. Hist. Nat. de Goethe, Paris, 1837), are joined the author's inter- 

 esting notes and anecdotes of later periods, down to 1831. The degenerescence 

 by diminution of vegetative force with renewals by generation, propounded 

 by Wolff, in Goethe's essay takes the form of successive expansion and con- 

 traction of organs. 



A. P. DeCandolle's Theorie file'mentaire de Botanique appeared in 1813, 



