CKfton College Scient7fc Society. 47 



whole tuft of leaves is seen emerging from the centre of the flower. 

 The carpels are sometimes found lymg spread out with buds, or 

 leaflets, in the place of ovules. 



In some cases the whole of the whorls of the flowers become leafy, as 

 in the green rose, or in diplotaxis tenuifolia, a member of the 

 cruciferous family, in which sepals, petals, stamens, and carpels, are 

 replaced by sixteen distinct leaflets, each in its ])roper position. 



Now, not only do we find the parts of the flower which are unlike 

 leaves in their normal condition assuming a leaf-shajie, but we also 

 occasionally find those parts which are more leafy, assuming the lorm 

 of the less leafy ones. The petals of the scarlet-runner have been 

 found turned into stamens, as also have those of the foxglove ; while 

 in papaver bracteatum a large number of the stamens are often 

 converted into pistils ; and in double-tulips all stages of the trans- 

 formation may be observed. The most curious case of such a change 

 is that which not unfi-equently occurs in the wall-flower. We 

 sometimes find the six new carpels perfectly fi-ee, lying spread open 

 with the rows of ovules along their inner edges ; occasionally the 

 edges are soldered together, and at other times the M'hole sei'ies are 

 united together into a tube surrounding the usual carpels. We see, 

 then, that each of the various whorls of the flower is sometimes I'ound 

 metamorphosed into another part, and also that they may each be 

 metamorphosed into leaves. 



These leaves, then, are the link which binds together the different 

 parts, at first sight each so unlike the other, but which, we have seen, 

 are really most intimately connected among themselves. 



This wonderful " lucky word whereby the riddle was read," was 

 further worked out by A. P. de Candolle, of Geneva, who, by con- 

 sidering some parts of the flower as degenerated, or absent by the 

 abortion of the buds which might have farmed them, and other paits 

 as formed of more than one organ cohei'ing together, held that all the 

 most irregular plants may be reduced to peifect s-ymmetry. 



I should, I fear, only weary you wei'e I to tell you of the almost 

 endless cases in which some of the most unsymmetrical flowers known, 

 such as the pea, the snapdi'agon, and the calceolaria, have been found 

 in a perfectly regular form; of hoAV, in some of the scrophulariace^ 

 some genera have five stamens, while in those which have a less 

 number we often find either a nearly perfect, though barren one, as in 

 pentstemon, or merely a thread often scarcely to be discovered, as in 

 antirrhinum, or how it has been shown that in the orchideae the 

 peculiir structure of the plant is owing to its having six stamens, of 

 which five are usually abortive. 



Is not this principle of metamorphosed symmetry a wonderful 

 simplifier of our difficulties ; does it not reduce contusion to order ? 

 such order as we find throughout the whole of nature. Not the order 

 of the parts of a dead machine (even though it be a machine endowed 

 with perpetual motion), but the order in which an intelligent being 

 works, adapting his means to his enils. Dees it not make the study 

 of Botany, which many of you probably associate only with sesqui 



