Water Cultures. 



251 



from which the wedge is cut. The wedge is held firmiy in 

 place by a small rubber band around the circumference of 

 the cork. The bottles are wide mouthed, of low form, hold- 



Fig. 10. Method of .starting growth :ind inateriuls used in water cultures 



of potatoes. 



ing about 250 cc. The stoppers fit tightly, which permits 

 no loss of water from the bottles except that transpired by 

 the plants. If desired a record of the transpiration can be 



