MICHIGAN EXPERIMENT STATION BULLETINS 



361 



liveforever move very slightly; m fact, many experiments convince us that 

 all growing leaves of all plants, even in still air, slowly move in various 

 directions all the time, day and night as long as they live. 



The action of light, heat or cold on the leaves causing the short thick 

 leaf-stems to move makes it seem as though plants had nerves and could 

 feel somewhat as can boys and girls and all animals, but no nerves have 

 ever been discovered. 



Hereafter, all of you will know that motion to some extent, is one of the 

 peculiarities of plants as well as of animals. 



I hope you will continue looking around to discover the positions taken 

 by all sorts of leaves, and stems, and flowers, and not let the subject drop 

 here. Keep notes in a book and make some drawings, and above all, tell 

 others what you discover and try to induce them to take an interest in the 

 work. 



Here are two illustrations of a few more kinds of leaves from a number 

 of different plants; in one the leaves are represented as usually seen 

 in the middle of a pleasant day, in the other as they appear in cool nights. 

 These drawings are taken from 'The Power of Movement in Flanis by 

 Charles Darwin. 



Fig. 36. a Leaf of wnod- 

 sorrell as seen from 

 above in the light of 

 day. 



b. The same as 

 seen at night. 



Fig. 37. a. Leaf of lupine as 

 seen from above in day- 

 light. 



b. A side view of th& 

 same as seen at 

 night. 



!&;n 



Fig. 38. a. Leaf of plant of 

 yellow melilot as seen from 

 above in the day time. 



b. The samp, in- 

 side view at 

 night. 



