402 The FroiJogation and Prevention of Smut 
Thus, we see tlae proportion of smutted ears bears no pro- 
portion to the number of spores adhering to the exterior of 
the seed. The large quantities of the spores dusted on the seed 
did not increase the number of bUglited ears, but the washed 
oats had a somewhat lower percentage of smutted ears. 
IV. Although, as is shown by the foregoing, it is impossible 
to infect oats and barley with smut spores to any appreciable 
extent by applying them to the seed-corn, yet there can be no 
doubt that the spores are the reproductive bodies of the fungus 
by which smut is propagated in nature. The subjoined table, 
showing the proportion of smut in 23 varieties of oats during 
three consecutive years on the Experimental Farm of the Royal 
Agricultural School near Copenhagen, leaves no doubt as to the 
unerring certainty with which the fungus is reproduced by 
nature : — 
Smut in 23 Varieties of Oats, 1885-87. 
Percentage of smutted ears 
Names o£ variety 
1883 
1886 
1887 
]. Canada 
28 
30 
22 + x 
1 
6 
9 
3. White Steier Mark 
1 
7 
12 
1 
3 
22 
0 
2 
6 
1 
7 
7 
0 
7 
13 
0 
0 
0 
1 
8 
14 
0 
6 
19 
0 
0-2 
4 
12. Great White Tartarian 
10 
10 
37 
13. Black Steier Mark 
0 
9 
9 
4 
5 
10 
10 
1.5 
20 
1 
6 
14 
8 
7 
28 
2 
3 
6 
19. New Zealand . 
22 
17 
21 
5 
6 
3 
21. Blainsly. . 
25 
45 
75 
1 
3 
8 
0 
4 
10 
It should be remarked that the seed was taken from the 
crop after it was cut, while the 2-3 varieties were lying side 
by side on the ground, so that there was no thrashing of the 
smutted and sound ears together, Avena strigosa was the only 
species absolutely free from smut. This, of course, means that 
