226 THE FLOWER. 



ground, they assume the aspect of creeping roots, and sometimes 

 form thickened rootstalks, as in the Calamus and Solomon's Seal, or 

 tubers, as in the Potato. But the type is readily seen through 

 these disguises. They are all mere modifications of the stem. The 

 leaves, as Ave have already seen, appear under a still greater variety 

 of forms, some of them as widely different from the common type of 

 foliage as can be imagined ; such, for example, as the thickened and 

 obese leaves of the Mesembryanthemums ; the intense scarlet or 

 crimson floral leaves of the Euchroma, or Painted-Cup, of the 

 Poinsettia of our conservatories, and of several Mexican Sages ; the 

 tendrils of the Pea tribe ; the pitchers of Sarracenia (Fig. 300), 

 and also those of Nepenthes (Fig. 301), which are leaf, tendril, and 

 pitcher combined. The leaves also appear under very different 

 aspects in the same individual plant, according to the purposes they 

 are intended to subserve. The first pair of leaves, or cotyledons, 

 when gorged Avith nutritive matter for the supply of the earliest 

 Avants of the embryo plant, as in the Almond, Bean, Pea, &c. (Fig. 

 108-120), Avould seem to be peculiar organs. But in some of 

 these cases, Avhen they have discharged this special office in ger- 

 mination, by yielding to the young plant the store of nourishment 

 Avith Avhich they are laden, they imi^erfectly assume the color and 

 appearance of foliage ; Avhile in other cases, as in the Convolvulus 

 (Fig. 123) and the Maple (Fig. 104), they are green and foliaceous 

 from the first. As the stem develops, the successive leaves vary in 

 form or size, according to the A-arying A'igor of Aegetation. In our 

 trees, Ave trace the last leaves of the season into bud-scales ; and in 

 the returning spring Ave may often trace the scales of opening buds 

 through intermediate states back again into true leaA'es (ICl)- 



426. The analogies of A"e";etation Avould therefore lead us to ex- 

 pect, that in flowering the leaves Avould be Avrought into ncAv forms, 

 to subserve peculiar purposes. In the chapter on Inflorescence, Ave 

 have already learned that the arrangement and situation of floAvers 

 upon the stem conform to this idea. In this respect, flowers are 

 absolutely like branches. The aspect of the floral envelopes favors 

 the same \-ieAv. We plainly discern the leaf in the calyx, and 

 again, more dehcate and refined, in the petals. In numberless in- 

 stances, Ave find a regular transition from ordinary leaves into sepals, 

 and from sepals into petals. And, Avhile even the petals ai-e occa- 

 sionally green and herbaceous, the undoubted foliage sometimes 

 assumes a delicate texture and the brightest hues (425). The per- 



