FEBRUARY 



161 



the dark. In both cases carbon dioxide is given off. 

 Why is it that oxygen does not mask the respiration 

 as before ? Because, since seeds are not green, no oxy- 

 gen is produced. 



In this experiment peas soaked over night, or, better 

 still, those already germinating, should be used. Fill 

 the jar at least a quarter full, and put in with the seeds 

 pieces of damp blotting paper to keep them moist. 



Do plants, like animals, breathe out water vapor ? 



An experiment ar- 

 ranged as in the accom- 

 panying cut will an- 

 swer the question. 

 Within twenty-four 

 hours the glass abov^e 

 the branches will be 

 covered with drops of 

 water. 



Care must be taken 

 to make the upper 

 tumbler air tight; 

 otherwise the water 

 transpired by the plant 



will be absorbed by 



the air, and in conse- 

 quence none will be deposited in the glass. This may 

 be done by fastening the upper tumbler to the pasteboard 

 with asphalt, shellac, or putty. 



CARD-BOARO 



To demonstrate that plants can feed upon solid lime 

 carbonate, plant a number of soaked peas on a piece 

 of polished marble in earth. At the end of a month, 



