286 Ward. — On Relations between Host and Farasite 
species and B. madritensis but not the others ; results quite 
in accordance with previous experience. 
If now we summarize the results of the infections in these 
three series — remembering that the method of infection and 
age of the plants used was the same in all, the only differences 
being in the dates of sowing and the after-treatment of the 
plants — some suggestive facts come to light, as the following 
Table XV shows. 
TABLE XV. 
Summary of Exp. Nos. 706-8. 
Species. 
Origin of 
spores. 
Results. 
706 707 708 
Incubation 
period. 
No. of infected 
plants showing 
pustules. 
B. mollis 
B. mollis 
+ 
+ 
+ 
9- 1 1 days 
28 
>> 
B. sterilis 
— 
— 
— 
0 
B. velutinus 
B. mollis 
+ 
— 
+ 
11-12 „ 
20 
99 
B. sterilis 
— 
— 
— 
O 
B. maximus ( 1 ) 
B. mollis 
+ 
— 
— 
19 » 
I 
„ (2) 
B. sterilis 
+ 
+ 
— 
13-19 » 
2 
B. sterilis ( 3 ) 
B. mollis 
+ 
— 
— 
19 » 
3 
99 
B. sterilis 
+ 
+ 
+ 
8-10 „ 
47 
B. madritensis 
B. mollis 
— 
— 
— 
0 
99 
B. sterilis 
+ 
+ 
9-ro „ 
33 
B. erectus ( 4 ) 
B. mollis 
+ 
— 
~ 
19 » 
1 
99 
B. sterilis 
— 
— 
_ 
0 
B. commutatus 
B. mollis 
— 
— 
+ 
12 „ 
5 
99 
B. sterilis 
— 
_ 
— 
0 
B. arvensis 
B. mollis 
+ 
+ 
+ 
9-r6 ,, 
20 
99 
B. sterilis 
— 
— 
_ 
0 
B. secalinus 
B. mollis 
+ 
+ 
+ 
n-16 „ 
11 
99 
B. interruptus ( 5 ) 
B. sterilis 
— 
_ 
— 
0 
B. mollis 
X 
— 
+ 
10-19 „ 
9 
99 
B. sterilis 
— 
— 
_ 
0 
B. racemosus 
B. mollis 
+ 
— 
+ 
n-12 „ 
9 
99 
B. sterilis 
— 
- 
- 
0 
( 1 - 5 ) Doubtful as to the positive result? 
The three experiments leave little room for doubt that 
under circumstances in which B. mollis is rapidly and easily 
infected by the spores from B. mollis (the incubation period 
being nine to eleven days), B. sterilis is either immune or 
only with difficulty and slowly infected by this fungus — e. g., 
after nineteen days in three cases out of about twenty (see 
Table XII). 
