192 



behaviour of the Papilionaeeae cannot be correct. New researches, 

 especially with Phaseolus, are desirable. 



From the preceding follows: 



For various Papilionaeeae, excelling by their abundance of nitrogen 

 connponnds, even when cultivated in media without such compounds, 

 tiie number and volume of the tubercles is so small, that if only 

 within them the tixation of free nitrogen should take place, the 

 intensity of the process in these tubercles must necessarily be very 

 great. We have not, however, succeeded gazometrically in observing 

 the process in the tubercles at all. 



Neither do the tubercle bacteria fix the atmospheric nitrogen when 

 cultivated out of the plant in nutrient liquids or in plate cultures, nor 

 enclosed in solid media'. 



The contradictory statements in the hand books of Flantphysiology 

 are erroneous. 



