WATER IN PLANTS. 89 



other at the back of the room where the light 

 is dull. The inside '.tf the upper glass standing 

 in the window soon becomes dull with water 

 settling on it and after a time actual drops of 

 water will trickle down. The one in the dull 

 .light remains bright much longer. The water 

 which settles on the inside of the glass must 

 come from the plant, for the card prevents the 

 water in the lower tumbler being evaporated. 

 We learn therefore that the leaves give off 

 water and that they give off more in the light 

 than in the dark Repeat this experiment 

 with a shoot from which the leaves have been 

 cut off and compare results. 



4. Take a tumbler, fill it half full of water 

 coloured with a little red ink. Place some 

 leafy shoots (balsams do admirably) with the 

 cut ends of their stems dipping in the water 

 and leave for a day. The stems become mark- 

 ed with red lines and finally the leaves also. 

 This colouration is due to the water which 

 passes up the bundles of the stem and their 

 continuation in the leaves (the veins) and. 

 being red, colours them, thus indicating the 

 path in the stem along which water travels. 



;">. Note the manner in which the leaves 

 of a sugar-cane roll up during dry weather. 

 This may also be observed by bringing a cane- 



