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superficial parts of the leaf, which has become converted into 

 the anther, while the filament corresponds to the petiole of the 

 common leaf. The fruit leaf is the upper and last stage of leaf- 

 metamorphosis, and here we find the three dimensions of the 

 leaf each changed in a peculiar way ; the sheath portion is 

 converted into the germ, the petiole into the style, and the 

 superficies into the stigma. The fruit leaf is in general not 

 situated at or near the axis, but exactly upon it, and conse- 

 quently the elongation of the axis is herewith at an end. 

 The axile formation takes part in the formation of the fruit 

 only in so far as it frequently ascends along the suture, which 

 is formed by the cohesion of the margins of the coelophyllum, 

 and becomes part of it. This is most evident when the pistil 

 is formed of several leaves. When the margins of each leaf co- 

 here inter se and with the intermediate ascending substance 

 of the axis, several cavities are formed in the germ ; but when 

 the margins of each single fruit leaf .do not cohere inter se 

 but with the margins of the neighbouring leaves, one cavity 

 is produced. The flower does not give rise to collateral axes 

 which remain adherent to the plant, but produces axes of pe- 

 culiar structure, which separate from the primitive axis and 

 commence an independent life ; these are the seeds whose de- 

 velopment before and after impregnation is treated of at some 

 length, according to the facts at present known. 



The leaves belonging to the series of the calyx and corolla 

 are to be regarded as leaves of two impulses following closely 

 one upon another. They are the peripherical parts of two 

 continuous portions of the stem which here indicate its me- 

 tamorphosis by the considerable contraction of the axis and 

 by the change in the form and colour of the leaves. The 

 calyx consists mostly of leaves which correspond only to the 

 inferior or sheath parts. They stand perhaps in the same 

 relation to the following more finely organized leaves as the 

 scales of the leaf-buds to their leaves. In a higher stage of 

 development the leaf becomes coloured ; in the young bud 

 the colour of the petals is generally of a light green. The 

 petal is however not a leaf metamorphosed in all its three di- 

 mensions, but it is especially the lamina or surface portion of 

 the leaf which is most developed, and the petiole is reduced to 

 the unguis in its development. When the petals are united in- 



