and Structure of Plants. 285 



The Fucus natans, the Conferva vagabunda, C. iEgagropila, 

 &c. are not only decidedly nourished thus, but are also unat- 

 tached and wandering plants, vegetable vagabonds as their 

 names import, being apparently destitute of root; while the 

 Tuber cibarium, or truffle, on the other hand, would seem to 

 be wholly root, it has neither stem, nor leaf, nor flower, nor 

 fruit ; and yet as the former are nourished without a root, so 

 in the latter the functions both of respiration and reproduc- 

 tion are essentially and effectually performed without even 

 the semblance of those organs which are elsewhere their pecu- 

 liar sites. Thus, in one type, e. g. y the Tremellse (nostoc), we 

 have nought distinct of any organ, or root, or stem, or leaf, 

 or flower, or seed; in another, as Tuber (cibarium), they are 

 all combined under the likeness of a root ; in the Confervae and 

 Fuci sometimes the similitude of leaf, sometimes of stalk, would 

 seem chiefly to prevail. In Testudinaria, the intermediate 

 caudex (in most plants so obscure) predominates ; while in 

 Aphyteia and Rafflesia little else, save flower, is known. In 

 the rushes and the cacti, the leaves are latent in the stem ; in 

 the lichens and the ferns, the reproductive germs are hidden in, 

 or united with, the leaf-like fronds ; while in the more common 

 and most developed plants, the root, the stem, the leaf, the 

 flower, the seed, are all distinct ; the root absorbs, the stem 

 upholds, the leaves respire, in short, each segregated organ is 

 found fulfilling its especial duty ; and neither performing, nor 

 fitted to perform, the function of another: and yet in some, an 

 occasional relapse is made in one or more particulars towards 

 that primitive universality of system, whence, after repeated 

 efforts, nature has extricated her superior works ; which re- 

 lapses are the intermediate links that establish an uninterrupted 

 connexion from the highest to the lowest grades. Thus floral 

 germs will grow, as in proliferous flowers, in continuation with 

 the parent stem, returning to the character of buds ; and gems 

 occasionally will loosen, and assume, in part, the functions pro- 

 per to seeds. Leaves and stalks will radicate at many points, 

 and by art be separable, or often separate spontaneously, into 

 many independent plants ; or, even without this violent discon- 

 tinuity ensuing, absorbents will detrude themselves on the 

 branches and trunks, even of forest trees, or pervade and cover 



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