8 



ELEMENTS OF BOTANY. 



In the second put blotting-paper that has been barely moistened ; on 

 this put seeds that have been soaked for 24 hours. 



In the third put water enough thoroughly to soak the paper : use 

 soaked seeds. 



In the fourth put water enough to half cover the seeds. 

 Place the vessels where they will have same temperature and note the 

 time of germination. 



Tabulate your results as in the previous experiments. 

 11. Experiment 4.*i Will Seeds germinate without Airf — 

 Place some soaked seeds on blotting-paper in the bottom of a bottle ; 

 close tightly with a perforated rubber stopper through which has been 



passed a long glass tube bent 

 once at right angles as shown 

 in Fig. 2. 



Exhaust the air from the 

 bottle by attaching the tube 

 to an air-pump or an aspi- 

 rator, and after considerable 

 pumping and while the ex- 

 haustion is going on, seal the 

 whole air-tight by heating the 

 tube near the bend with a 

 Bunsen burner or alcohol 

 lamp flame until it can be 

 drawn out to a thread. 



The stopper will be more 

 certain to prove air-tight if 

 it has been well moistened 

 with glycerine or vaseline before being inserted in the bottle. 



Place other seeds of the same kind in another bottle and stopper 

 tightly. 



Place other seeds of the same kind in a third bottle ; stopper loosely. 

 Place the three bottles side by side, so that they will have the same 

 conditions of light and heat. Watch for results, and tabulate as in 

 previous experiments. 



Most seeds will not germinate under water, but those of the sun- 

 flower will do so, and therefore Exp. 4 may be varied in the following 

 manner : 



Pig. 2. — Soaked Peas in Stoppered Bottle, 

 ready for Exhaustion of Air. 



1 Experiments maiked thus * are to he performed hy the teacher in the lahoratory 

 pr class-room. 



