STORAGE OF FOOD IN THE SEED 21 



EXPERIMENT III 



Will seeds germinate well without a good supply of air ? * * 



A. Place some soaked seeds on damp blotting paper in the 

 bottom of a bottle, using seeds enough to fill it three quar- 

 ters full, and close tightly with a rubber stopper. 



B. Put a few other seeds of the same kind in a second bottle, 

 and cover loosely. Place the 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. 



EXPERIMENT IV 



Effect of germinating seeds upon the surrounding air.* * When 

 Exp. Ill has been finished remove a little of the air from above 

 the peas in the first bottle. This can easily be done with a rubber 

 bulb attached to a short glass tube. Then bubble this air through 

 some clear limewater made by slaking quicklime in warm water 

 and filtering through a paper filter. Also blow the breath through 

 some limewater by aid of a short glass tube. Explain any similar- 

 ity in results obtained. (Carbon dioxide turns limewater milky.) 

 Afterwards insert into the air above the peas in the same bottle 

 a lighted pine splinter, and note the effect upon its flame. 



STOEAGE OF FOOD IN THE SEED 



EXPERIMENT V 



Are the cotyledons of a pea of any use to the seedling? Sprout 

 several peas on blotting paper. When the plumules appear 

 carefully cut away the cotyledons from some of the seeds. Place 

 on a wide, perforated cork one or two seedlings from which the 

 cotyledons have been cut, and as many which have not been 

 mutilated. Put the cork in the mouth of a cylindrical glass jar 

 of water, which it should fit moderately well, and allow the roots 

 to extend into the water, which must be kept always at the same 

 level. Let them grow for some weeks and note results. 



