168 THE FLOWER. 



gous with leaves ; that the sepals are comparatively little, the 

 petals more, and the reproductive organs much modified i'roin the 

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

 is meant hy the proposition that all these organs are transformed 

 or metamorphosed leaves. What would have been leaves, if 

 the development had -one on as a vegetative branch, have in 

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

 tions. Limueus expressed this idea, along with other more 

 speculative conceptions, dimly apprehended, by the phrase Vege- 

 talile .Metamorphosis. Not long afterwards, this fecund idea 

 of a common type, the leaf, of which the parts 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 Grcthe, in a long-neglected but now well- 

 known essay, on the Metamorphosis of Plants. Twenty-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 foliaceons 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 : 



I'lumulam seminis saepius terminal aut flos aut gemma. 



Principium florum et foliorum idem est. 



Prindpiuni gemmarum et foliorum idem est. 



Gemma constat foliorum rudiment is. 



Periantliium sit ex connatis foliorum rudimcntis. 



His dissertation, Prolepsis I'lantarum, in Anwn. Acad. vi. (1700), added 

 nothing hut obscure speculations to the former comparatively clear 

 statements. 



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

 mainly concerning animals, published in 1750, 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-M-iles or tloral 

 organs, as the ease may he, through degciiercscence or diminution of vege- 

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



Johann Wolfgang (Jothe's Yersneh die Metamorphose der Prlan/cn zu 

 erkliiren was published in 17'.M). in 8(5 pages. For the translations and 

 reproduction.-, see Prit/.el, Thesaurus. To tin- Kreiich translation by Soret. 

 with (Jerman text accompanying (Stuttgart, ls:!l), and a No to that of Ch. 

 Martens |(Kuv. I list. Na t. de ( iirthe, Paris, 1837), are joined the author's inter- 

 esting notes and anecdote- of later periods, down to 1 S-">1. The degcncrescence 

 by diminution of vegetative force with renewals by generation, propounded 

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

 traction of organs. 



A. P. DeCandolle's Theorie El&nentaire de Botanique appeared in 1813, 



