328 



HUTCHINSON'S POPULAR BOTANY 



the "White Water-lily (Nymphona alba\ in which the gradual stages of 

 transformation from the green sepals of the calyx to the yellow pollen- 

 producing stamens may be seen to great advantage. We are not speaking 

 now of ' ; monstrous " specimens of the flower (nor were the Begonia and 

 Clematis last alluded to at all abnormal), but of the ordinary White Water- 

 lily ; which thus shows, in a permanent fashion, the community which 

 exists between the various members of the flower. For the sepals merge 

 into petals, and the petals into stamens, by such imperceptible gradations 

 that at certain points it is difficult to say to what set of organs particular 

 parts belong. In drawings made to illustrate the fact, it is easy enough to 

 see that one figure with its dark green colouring is a sepal, and that a second, 

 though of a paler green, is probably a sepal too; but what of the next 



figure ? This is neither 

 a decided green nor a 

 pure white, but a cross 

 between the two, and 

 it might be called in- 

 differently a sepal or a 

 petal. In the next row 

 we have petals beyond 

 a doubt ; but we are 

 again at a loss when we 

 come to another row. 

 Do these organs repre- 

 sent petals or stamens ? 

 They are broad and 

 white like the former 

 row, but the thickening 

 at their apex is of a 

 3 T ellow colour, and has 

 all the appearance of 

 rudimentary anther- 

 lobes. The figure beside it is equally perplexing, and not till we get far 

 in do we find a stamen pure and simple, with normally developed style 

 and anther and abundance of pollen. The transition is far more 

 gradual than the description might lead one to suppose. In the flower 

 itself a large number of petaloid sepals and stameniferous petals have 

 place between the organs named; and each differs in some slight 

 degree from its neighbour. Here, then, you have an abiding witness to 

 the facts of which we have been treating a constantly accessible illustration 

 of that homology of structure which seems to exist between the members 

 of every flower. We are now in a position to carry our inquiry a step 

 farther. 



A flower being only a modified shoot, it is not surprising that the 



Fio. 398. FLOWER OF Clematis ccerulea, 

 With petaloid sepals. 



