PLANTS WITHOUT CARBON DIOXIDE 



229 



plant when cultivated without carbon dioxide, with that of others 

 deprived of mineral salts. 



297. Culture of Plants in Atmosphere Lacking Carbon Dioxide. 

 A bell-jar with a tubulure at the top is necessary to carry out 

 this experiment as described. The tubulure is closed with a 



FlG. 113. Apparatus for growing plants in an atmosphere free from carbon dioxide. 

 I, dish containing solution of potassium hydrate. 2, specimen of Arisaema triphyllum 

 ten days after opening of bud. 3, receiver of ten liters capacity. 4, outlet-tube 

 connected with aspirator. 5, sticks of potassium hydrate and moist asbestos fiber. 

 6-9, details of method for sealing plant in receiver. 6, cork. 7, asbestos fiber. 8, 

 mercury. 9, stem of plant. 10, sponge saturated with water. 



stopper containing an outlet tube connecting with an aspirator or 

 filter pump, and an inlet tube connected with a cylinder filled 



