JOURNAL 
OF THE 
ROYAL AGRICULTURAL SOCIETY 
OF ENGLAND. 
THE SOURCES OF THE NITROGEN OF 
OUR LEGUMINOUS CROPS. 
Contents. 
llffTBODUOTION 657 
EABLIEK EXPERIMENTS, WHICH MD NOT PFOW FIXATION OP FtlEE 
NITItOGEN 6G6 
EECENT EXPERIMENTS, WHICH DO SHOW FIXATION OF FREE NITRO- 
GEN G69 
THE VEGETATION EXPERIMENTS IN 1888 670 
THE VEGETATION EXPERIMENTS IN 1889, 1890, AND 1891 . . 678 
DIFFERENCE IN THE EXTERNAL CHARACTER OF LEGUMINOUS ROOT- 
NODULES 687 
HOW IS THE FIXATION OF NITROGEN TO BE EXPLAINED? . . . 689 
OF WHAT IMPORTANCE TO AGRICULTURE IS THE NEWLY-RECOGNISED 
SOURCI! OF NITROGEN TO LEGUMINOUS CROPS? , , . 69G 
Introduction. 
It happens that the agricultural plants belonging to the great 
family of the Leguminosce are all included within the sub- 
order Painlionaceoi. But as the terms Legiiminosce and legumin- 
ous are better known in agricultural discussions they will be 
adopted throughout this article. It will be seen farther on, 
however, that the limitation which the use of the terms Papilio- 
nacece and painlionaceous would imply, may possibly in the course 
of future investigation prove to be more appropriate, especially 
\^ VOL. II. t. S. — 8 X X 
