New YorK AGRICULTURAL EXPERIMENT STATION. 37 
able number of plants should be examined before concluding as to 
the amount of inoculation present in a field. 
Presence of nodules in the uninoculated fields — Examination of 
the 67 check plats showed the presence of nodules on at least a few 
of the plants in all but 5 plats. Two of these plats were among 
those not seen by a Station representative, the reports having been 
made by the co-operating farmers. The fact that nodules were 
found by the same farmers on their adjoining inoculated plats shows 
that they understood what they were looking for and they would 
probably have found the nodules had they been present in any con- 
siderable numbers. However, the repeated failure of other farmers 
to find the nodules where we later found them present in small 
numbers would suggest that there may have been a few tnoculated 
plants that were overlooked in these check plats. In one case 
where we examined a check plat without finding any inoculated 
plants the check plat was such a failure that all of the plants were 
dead and the land ploughed; so there was nothing left to examine. . 
The dryness and hardness of the soil were probably responsible 
for the failure to find any nodules in the other two fields. On 
each of these five check plats the alfalfa crop was a failure. 
While it should not be forgotten that the adjacent inoculated 
plats contributed in some cases to the inoculation of the check plats, 
the fact that some inoculation was practically everywhere present 
and the way that the inoculated plants were distributed over the 
plats make it probable that at least a small amount of natural inocu- 
lation is present in all cases. 
Source of this widespread inoculation One explanation for 
the wide distribution of these germs which has been here observed 
is that the bacteria are carried upon the seed. When the slight 
contact which the seed has had with the soil is remembered in con- 
nection with the rapidity with which the legume bacteria are killed 
by drying it would seem that this method of transportation ts 
highly improbable. However, Ferguson** states that legume bac- 
teria are carried upon seed and in a personal letter explains that he 
has recovered them from commercial alfalfa seed by laboratory 
methods. This would seem to settle the fact that they are some- 
times carried in this way; but the results which will be given under 
the heading, “ Inoculation by living cultures placed upon the seed,” 
tend to show that seed is poorly adapted for transporting these 
4 See footnote 22. 
