THE ORIGIN OF FLOWERS. 



159 



needful that the bunch of colored leaves should 

 be so placed as to guide the insect toward the 

 pollen and ovules. Hence we find a great variety 

 in the portions of flowers which are thus dec- 

 orated with brilliant tints. The stamens and pis- 

 til themselves rarely take part in this function of 

 attraction, though sometimes even these working 

 organs are brightly painted with pink, yellow, or 

 pearly white. In such plants as the mallow, the 

 bramble, the tulip, the fuchsia, the mignonette, 

 and the clematis, the stamens and pistil form very 

 conspicuous portions of the attractive organ. 

 More frequently, however, the corolla, or petal- 

 whorl, which succeeds the fructifying structures, 

 is alone intrusted with the special function of al- 

 luring insects by its hue. This is the case with 

 the buttercup, the pink, the pea-tribe, the rose, 

 the poppy, the violet, and the great mass of or- 

 dinary flowers in general. Indeed, one may say 

 roughly that the popular conception of a flower 

 is mainly founded upon the corolla, while the 

 botanical idea of an inflorescence is mainly found- 

 ed upon the stamens and pistil. But in a consid- 

 erable number of plants the coloring of the corol- 

 la is not by itself sufficient to allure the fertiliz- 

 ing visitors, and so the calyx, or outer whorl, 

 originally a protective sheath for the blossom, is 

 sometimes diverted wholly or in part to this sec- 

 ondary function. In the milk-wort we see an 

 early stage of such a process, where only a por- 

 tion of the calyx is devoted to the purpose of al- 

 lurement ; but in the fuchsia it is the calyx which 

 forms the principal and most brightly-colored 

 feature on the whole flower. Then, again, a large 

 number of blossoms have only a single duplicate 

 whorl to represent both calyx and corolla, in 

 which case we sometimes conclude that the two 

 original whorls have coalesced, and sometimes 

 that the plant never possessed more than one. 

 Instances are to be found in the tulip, the hya- 

 cinth, and most so-called lilies. Lastly, we have 

 in the arum a white or purple sheath which in- 

 closes a whole group of little inconspicuous blos- 

 soms, but performs exactly the same function as 

 the petals in attracting the insect eye. 



The most conclusive fact, however, in favor 

 of the purely functional origin here assigned to 

 the colored leaves is to be found in the case of 

 certain plants whose true flower, being small and 

 inconspicuous, is surrounded by an irregular sup- 

 plementary mass of brilliant leaves. The best- 

 known instance of this peculiarity is the scarlet 

 poinsettia, which has an insignificant little yellow 

 blossom, so small that it could hardly strike even 

 the microscopic eye of a tropical butterfly. But 



the comparative poorness of the true flower is 

 made up for by a magnificent bunch of scarlet 

 leaves, which terminate every flower-bearing 

 branch, and are far more striking than the yel- 

 low blossom could ever hope to become, even if 

 immensely increased in size and brilliancy. In 

 the midst of this scarlet bunch the flowers nestle 

 securely, and trouble themselves no more about 

 the disposal of their pollen. An equally instruc- 

 tive though less beautiful example is offered by a 

 little West Indian plant, whose tiny blossom is 

 surrounded by three green bracts, while the upper 

 surface of each bract has a patch of red pigment, 

 daubed, as it were, over its face. If you turn up 

 the leaf, you see that the pigment does not pene- 

 trate to its lower surface, so that at first you have 

 great difficulty in rejecting the belief that some 

 mischievous painter has been playing you a trick 

 by deftly spreading a little patch of color in the 

 centre of each bract. Of course, the conclusion 

 toward which all these facts point is a very simple 

 one — namely, that if a tendency to the production 

 of bright colors in the neighborhood of the repro- 

 ductive organs is once set up, no matter in what 

 portion of the plant it may occur (whether in 

 stamens, corolla, calyx, sheath, bracts, or leaves), 

 it will be perpetually strengthened and further 

 developed by natural selection, provided it proves 

 useful to the plant in promoting cross-fertilization 

 through the agency of insects. 



Nor does the process stop here. Some flowers 

 are not sufficiently conspicuous to attract separate 

 attention on their own account, but they manage 

 to do so by massing themselves together in con- 

 siderable bunches. This massing can be simply 

 effected, as Mr. Herbert Spencer has pointed out, 

 if the internodes (or pieces of stem between each 

 blossom) are permitted to become dwarfed. We 

 see the first instance of such dwarfing in a spike, 1 

 like that of the foxglove, the snap-dragon, the 

 gladiolus, and the orchid. In the head, the dwarf- 

 ing has proceeded a step further, as exemplified 

 by clover. To one or other of these or similar 

 classes belong those conspicuous bunches of blos- 

 som which we find on the lilac, the horse-chest- 

 nut, the wisteria, the laburnum, the rhododendron, 

 and indeed almost all our most noticeable flower- 

 bearing plants, domestic or exotic. The umbel- 



1 1 must warn the reader that I am intentionally 

 and consistently avoiding the cut-and-dried phrase- 

 ology of botany, iu favor of simpler though less exact 

 terms. He will learn with pleasure from any botanical 

 critic that the proper expression in this case would 

 have been a raceme. Having made this apology once 

 for all, I trust I may be permitted to continue unmo- 

 lested in a tongue understanded of the people. 



