in the Bromes and their Brown Rust. 241 
I have found the fungus thus described on the following 
plants : — B. mollis , common and very strongly developed both 
in the open fields and in the garden; B. sterilis, equally 
common, though the pustules on the wild plants in the 
hedgerows and fields were never so strongly developed or 
so large as on the wild B. mollis . In the gardens, on well- 
grown plants, they were sometimes equally good however. 
On B. secalinus , in the garden only, where the pustules were 
finer than any others. B. brizaeformis , only in the Botanic 
Garden, and strongly developed. On B. arvensis , B. macro- 
stachys , B. brevirostratus , B. longiflorus i and B. purpureus , 
all growing in the gardens in tufts close to those already 
mentioned, the pustules were fewer and, as a rule, less well- 
developed. 
I have failed to observe this fungus on B. inermis , 
B. echinaceus , B. madritensis , or B. maximus , even on tufts 
growing close to and intermingled with those mentioned. 
On a species marked B. asper , in the gardens, but which 
turned out to be B. arvensis when critically examined in 
flower, a second Uredo was equally common with that of the 
Brown Rust, Puccinia dispersa , viz. P. glumarum , the Yellow 
Rust, a point of some importance in connexion with certain 
experiments. 
This confusion of names also brings prominently forward 
the necessity of having perfectly accurately named ‘ seed ’ of 
the varieties and species to be experimented with, and I had 
to go into this question very carefully in preparation for what 
follows. 
3. On the Species of Bromus used in 
the Experiments. 
Hackel, following to some extent Bentham and Hooker 1 , 
divides the genus Bromus into five subgenera as follows : — 
(1) Festucoides. Perennial, mostly tall and with loose 
panicles. The first glume 1 -nerved, the second 3-nerved. 
1 See Genera Plantarum, vol. iii, p. 1200, and Hackel, Die natiirl. Pflanzen- 
familien, 11. Th., 2. Abt., p. 75. See also Ascherson, Syn. d. mittel-europ. FI., 
1901, p. 574, for a critical review and differences in detail. 
