THE PLANT IN ACTION. 267 



the upper side of the outstretched stem, and see if 

 the dots continue in that position. 



Make a circuit of the garden and grounds in the 

 daytime, and note the appearance and position of 

 the leaves of each of the plants you encounter. Ob- 

 serve the attitude of the petiole and the blade, and 

 the degree of flattening that the leaf exhibits. Note, 

 also, the state of the floral organs. Observe them 

 again in the evening, or at nightfall. Flowers that 

 were open by day, and are now closed, should be ob- 

 served again on the following day, to see if they re- 

 open. If they do, watch them, and discover their 

 times of opening and closing. If they do not, dis- 

 cover, if you can, how long they remain open. 



Have the leaves of any of the species observed in 

 the daytime assumed a different position ? 



When certain movements of leaves and petals, as 

 curvature or folding, take place at particular times, 

 and the new position is retained for a certain period, 

 such movements are called the sleep of plants. 



