in the Bromes and their Brown Rust. 283 
TABLE XII. 
Exp. No. 706, June 4, 1901. * Seed ’ sown May 27. Bromes infected on tips of seed- 
lings just (2-15 mm.) above ground, germinated under hand-glass in garden. In- 
fected plants put outside, under bell-jars, after 48 h., in N. light, then (after a week) 
exposed. Get sun about 2 hours at mid-day. Normal plants, though small. 
Species. 
Origin of 
spores. 
Results. 
Approximate 
No. of plants 
infected. 
Incubation 
period. 
No. of leaves 
with pustules 
on 1 9 th day. 
Period of 
observation. 
B. mollis 
B. mollis 
+ 
20 
11 days 
10 
21 days 
99 
B. sterilis 
— 
20 
0 
9 9 
B. velutinus 
B. mollis 
+ 
20 
11 *> 
19 
a 
99 
B. sterilis 
— 
20 
0 
9) 
B. maximus (1) 
B. mollis 
+ 
?* 
19 „ 
I 
99 
„ (2) 
B. sterilis 
+ 
? 
19 » 
1 
99 
B. sterilis (3) 
B. mollis 
+ 
? 
19 »> 
3 
99 
99 
B. sterilis 
+ 
? 
10 „ 
18 
99 
B. madritensis 
B. mollis 
— 
20 
0 
99 
)) 
B. sterilis 
+ 
15 
10 „ 
14 
99 
B. erectus (4) 
B. mollis 
+ 
10 
19 „ 
99 
„ * (5) 
B. sterilis 
— 
10 
0 
99 
B. commutatus 
B. mollis 
— 
20 
0 
99 
B. sterilis 
_ 
20 
0 
99 
B. arvensis 
B. mollis 
+ 
12 
11 „ 
10 
99 
B. sterilis 
— 
12 
0 
9 9 
B. secalinus 
B. mollis 
+ 
8 
11 „ 
6 
99 
9 9 
B. sterilis 
_ 
15 
0 
99 
B. interruptus (6) 
B. mollis 
+ 
20 
19 „ 
2 
99 
)) 
B. sterilis 
— 
20 
0 
99 
B. racemosus 
B. mollis 
+ 
10 
11 „ 
6 
99 
B. sterilis 
- 
10 
0 
99 
(1-3) Must be regarded as doubtful ? 
(4) Must be regarded as doubtful ? (5) 10 infected. 
(6) Must be regarded as doubtful ? 
* About 20, but not exactly recorded. 
lings slightly forced in the intermediate pit, and kept during 
incubation in a damp shady corner where they never got 
direct sunlight at all. The plants were much drawn, slightly 
pale in colour, and very succulent — i.e. they were more or 
less slightly etiolated. The principal differences were the 
very poor pustules developed and fewer positive .results. In 
some cases — e.g., B. arvensis and B. secalinus — the period 
of incubation seemed to be lengthened, while in others no 
comparison seems possible. 
As the Table XIII shows, the spores of B. mollis infected 
B. mollis readily and B. arvensis and B. secalinus more slowly, 
but they did not successfully attack B. velutinus and B. race - 
U 2 
