298 DR. M. J. SCHLEIDEN ON PHYTOGENESIS. 



of a value not exhibited in specie^ in order to facilitate commerce. 

 And to carry the comparison further, there follows an insecurity 

 in this intellectual property, and frequently bankruptcy, if this 

 coinage has not its unchangeable, accurately determined stand- 

 ard : in a word, the utility of a scientific expression depends on 

 the accurate definition of the idea upon which it is based. Un- 

 fortunately the perversity of our social relations has made us 

 entirely forget the original meaning of money ; the sign has be- 

 come to us the thing itself: may some good genius preserve us 

 in our intellectual life from similar mistakes! We must here 

 guard against two dangerous rocks ; first, when words are trans- 

 ferred fi'om one science to another without accurately testing 

 whether they fit in their new place as to all their accompanying 

 meanings also ; and secondly, when we lose sight of the signi- 

 fication of a word consecrated by the spirit of the language and 

 its historical development, and employ it without any further 

 ceremony in compounds, where perhaps, at most, only an unes- 

 sential part of its signification suits. 



Thus, for instance, E. Meyer {Linnceaf vol. vii. p. 454.), after 

 repeating the well-known experiments of Duhamel, lays down 

 this position : " the law of the longitudinal growth of the inter- 

 nodes is, to grow inter se, or from above downwards.^' This po- 

 sition he requires for his theory, and consequently he must de- 

 fend it in all ways, although he himself confesses that this re- 

 verse growth must appear to every one of his readers contrary 

 to good sense. He would never have arrived at this position if 

 he had more accurately analysed the word " grow,'^ (to which he 

 was accustomed in animal physiology,) in reference to its appli- 

 cability to the plant : he would soon have found that the origin 

 of new cells, and consequently the actual growth of the plant, 

 constantly takes place in its outer portions upwards, and that 

 his very comparison of the building up of a voltaic pUe is ex- 

 ceedingly well adapted to refute himself. Nothing further would 

 result from the experiments of Duhamel and Meyer, than that 

 the inferior, i. e. precisely the first originated, older cells of the 

 internode possess a greater power of extending in the longitudi- 

 nal direction, and retain this capability longer than the younger 

 cells. 



With respect to the second point, we find an admirable exam- 

 ple in the position frequently expressed of late, that the stem of 

 the plant is formed of the cohering petioles. The word " cohere" 



