484 HISTORY OF PHYSIOLOGY. 



might have formed them, and other parts as adher- 

 ing together, he holds that all plants may be re- 

 duced to perfect symmetry: and the actual and 

 constant occurrence of such incidents is shown 

 beyond all doubt. And thus the snap-dragon, of 

 which we have spoken above, is derived from the 

 Peloria, which is the normal condition of the flower, 

 by the abortion of one stamen, and the degeneration 

 of two others. Such examples are too numerous 

 to need to be dwelt on. 



Sect. 2. Application of Vegetable Morphology. 



THE doctrine, being thus fully established, has been 

 applied to solve different problems in botany ; for 

 instance, to explain the structure of flowers which 

 appear at first sight to deviate widely from the 

 usual forms of the vegetable world. We have an 

 instance of such an application in Mr. Robert 

 Brown's explanation of the real structure of various 

 plants which had been entirely misunderstood : as, 

 for example, the genus Euphorbia. In this plant 

 he showed that what had been held to be a jointed 

 filament, was a pedicel with a filament above it, 

 the intermediate corolla having evanesced. In 

 Orchidece, (the orchis tribe,) he showed that the 

 peculiar structure of the plant arose from its having 

 six stamens (two sets of three each), of which five 

 are usually abortive. In Coniferce, (the cone -bear- 

 ing trees,) it was made to appear that the seed was 



