37 G THE UNIVEKSE, 



which expand to the bosom of the atmosphere. The same 

 organ therefore is at once trunk and root. 



Experiment proves this fact still better. Duhamel in- 

 verted Avillows, placing their roots in the ojien air and 

 their boughs in the earth. So identical are these organs^ 

 that in a short time the roots were covered with leaves, 

 and the stems, transformed into an underground structure, 

 had ]mt out spongioles. This curious experiment suc- 

 ceeded equally well on a large scale. M. de Eaguse, in 

 his memoirs, mentions having seen on the property of a 

 Russian gentleman, an avenue of limes which he had in a 

 Avliim transjjlanted upside down. The metamorphosis was 

 complete ; all the inverted trees bloomed splendidly, and 

 the roots were comj)letely changed into vigorous leafy 

 branches.^ 



The identity between the organs is so complete that the 

 physiologist can even transform the middle part of the stem 

 into a root, whilst above and below this it puts out branches 

 covered with leaves, in such a manner that the tree thus 

 represents two trees placed one above the other. Duhamel 

 proved this by a curious experiment. He surrounded the 

 stem of a Avillow with a cask filled with earth, which was 

 raised from the ground to a higher level than the first 

 branches of the tree. Adventitious roots soon shot out on 

 this part of the trunk, while al:)0ve and below it was laden 

 with boughs covered with verdure. 



Anatomy assigns generally three functions to the 

 roots : they fix the tree, feed it, and at the same time fill 

 the office of excreting organs. 



1 In the birch-wood of Culloden there is a lareh-fir wliich was blown down 

 in a storm, and fell across a gully. Tlie branches took root on the other 

 side, and from the parent stem, thus fed, shot up perpendicularly fifteen trees 

 all in a row, and which still flourish in all their splendour.— ,S'ae)toe Gossip 1S6S. 

 — Tr. 



