LECTURE XXXI. 



53^ 



in my experiments in 1863) the buds of plants provided with numerous leaves 

 into a dark box, in such a way that the shoots which proceeded thence must 

 develope inside it, while from numerous leaves, which were as large as possible 

 and exposed to the most intense light available, the products of assimilation outside 



FIG. 345.—^ B C a Gourd-plant ; AT AT a large wooden box, in which the part B of the plant is 

 etiolated in the dark (cf, text on p. 3^5). 



were transmitted to them ; thus in proportion as the growth in the dark progressed, 

 substances available for growth were also formed by the assimilation of the illumi- 

 nated leaves, and carried to the places where they were used. Fig. 345 illustrates an 

 experiment of this kind, as I am in the habit of arranging it for the purposes of 

 demonstration. After all the axillary shoots have been cut away from an already 



