The Sex and Generative Organs of Plants, 265 



ent colour and shape, and by a more delicate structure, 

 from the green leaves ; and the stalk, on whose summit 

 it is arranged, differs from the common stalk, in the pro- 

 portionately smaller mass, and in the greater fineness and 

 tenderness of its structure; in consequence of which, 

 it does not last longer than the fruit, and in comparison 

 with other branches, receives but small woody deposits. 

 The leaves too of the calyx and of the corolla, the anthers 

 and the pistil, are equally real leaves, just as the stalk 

 of the flower is a real branch. Of these parts we can 

 very often satisfy ourselves, from the so-called monstrous 

 flowers, in which we see in different stages the metamor- 

 phosis of the leaves into the parts of the flower, or from 

 the case of the stalk, which we see sometimes grow on into 

 a real branch with green leaves. 



While in the regular flowering of a plant, each of these 

 transformations of a leaf takes place in a certain order of 

 development, and suddenly and at once ; in such irregular 

 cases, we find one or other of the same leaves in different 

 stages of development, as partly green and partly coloured, 

 and the whole succession of the different transformations 

 in hke manner disturbed. All this we often observe in 

 cultivated plants, such as tulips and roses. The stalk, how- 

 ever, in the process of formation of a flower does not by any 

 means undergo such varied changes as the leaves ; neverthe- 

 less it becomes a changed organ. Its most important con- 

 dition is, as already remarked, that on the appearance of the 

 flower leaves, the tendency to growth in length ceases in its 

 stem and its branches. The stalk, so soon as the flowering 

 process commences with the appearance of the calyx, 

 becomes much shortened and contracted, so that it now 

 only appears a small knot among the leaves of the flower. 

 This is the so-called receptacle. Thus then the stalk or 

 twig completes with the appearance of the flower its growth 

 in length. 



