BY SUBDIVISION. 191 



that these germs are of two distinct species, the one pro- 

 ducing stems, the other roots. The former originate 

 chiefly in the axilla of the leaf, or part which unites the 

 leaf to the stem ; and which, from the analogy it bears to 

 the union of the arm to the body in the human frame, is 

 called the axilla : the latter shoot out roots on each side. 



It has been affirmed that roots may, by exposure to the 

 air, be converted into branches ; and branches, by being 

 buried in the earth, transformed into roots ; and this, 

 as I believe I before mentioned to you, has been attempt- 

 ed to be proved by overturning a willow, burying the head 

 in the ground, and leaving the roots upwards exposed to 

 the air. But what was the result ? Not that the branches 

 became roots, and the roots branches ; for the former be- 

 ing unfurnished with the organs of absorption, and the 

 latter with those of evaporation, it was impossible for them 

 to exchange their respective functions ; but the branches 

 being deprived under ground both of light and air, and of 

 all the circumstances favorable to the developement of 

 the germs of other branches, these branches do not shoot. 

 The same circumstances being, on the other hand, par- 

 ticularly adapted to the developement of the germs of 

 roots, these strike out into the soil. 



In the mean time the roots, which have been compelled 

 to change places with the branches, being exposed to the 

 light and air, and so situated as to favor the developement 

 of the germs of branches, and in direct opposition to that 

 of the germs of roots, shoot out young branches from their 

 naked roots, and in the course of time cover them with 

 foliage. 



Emily. I recollect having seen the leaf of a plant, 

 which, when simply laid upon moist ground, struck out 

 roots from its edges into the soil. 



Mrs. B. This is the Bryophyllam : The flower is the 

 only part of a plant which is incapable of developing either 

 a root or a stem, except through the medium of the seed, 

 the production of which is its sole and exclusive function. 



There are three modes of multiplying plants by di- 

 vision : 



1046. How do these two species of germs originate! 1047. What 

 unnatural change, has it been affirmed may be caused with certain trees'! 

 1048. When the experiment was made with the willow what was the re- 

 sult upon the branches! 1049. And upon the roots'? 1050. What 

 is said of the Bryophyllaml 



