THE ROOT. 107 



in performing the various operations peculiar to organized 

 beings. We have seen that the whole vegctahle kmt'dom. 

 however various in tbrin and constitution, liad its origin, at 

 least, in njinute visicles. We have also seen that all the or- 

 gans of reproduction and nutrition, are simple moditications 

 of leaves. Who can fail to admire the wisd«jm ot" that Beintr, 

 who could construct with materials so simj)le, the endless vari- 

 ety of vegetable organs, and make them yield products of 

 every variety from the blandncss of water to the most pow- 

 erful agents ; and to atlbrd nutriment to men and animals, 

 and deposit cotcmporaneously and contiguously the most vir- 

 ulent poisons ! 



Our next object is to consider plants as living beings, and 

 so far as possible to explain the various phenomena connected 

 with them as such. ^ 



Section 1. The Root. 



130. The tirst organ that appears in the germination ofa seed 

 13 the root. It bends downwards, and soon commences the 

 proper tunclions tor which it is intended, that of absorbino- 

 nourishment from the medium which it penetrates, and giving 

 support to the plants. These seem to be the only functions 

 wijich the root performs. It lengthens by additions to its ex- 

 tremity, which always consists ot" an enlarged portion of cel- 

 lular tissue, Ijetbre described under the name of spongiole. 

 Through this extremity all the nourishment of the plant which 

 is absorbed trom the soil passes, as we demonstrated in a for- 

 mer section. 



131- The root has no power of selecting its food. This 

 is rendered evident by making various solutions, and wa- 

 tering the plant with them. It absorbs them indiscriminate- 

 ly ; the onlv conditions being that thev do not act on ve^et- 

 • able substances, and that they be in a fluid state. The con- 

 trary of this has been the opinion in former times. It has 

 been thought that the root not only had the power of se- 

 lecting approppiaic food lor the plant, but also of searching 

 tor it. The experiment of planting a Strawberry in a sandy 

 soil, surrounded by rich earth, but not coming in contact with 

 it, when it was fo^nd that the roots immediately sought the 

 rich earth, was considered conclusive on this point. But the 

 explanation of this phenomenon is easy without having recourse 

 to any power or instinct on the part of the root for seeking nour- 

 ishment. The influence of the rich soil was lelt by the 

 oots, although not in contact, and they became stimulated 



