412 Transactions. 
Infection.—According to Osner, healthy plants become infected through 
the flowers, as is the case with wheat or barley infected wit ritici. 
Following infection the hyphae remain quiescent in the seed until they 
germinate, when they grow out with the developing leaves and stems. 
These hyphae give rise to the linear sori ; those that grow with the growing- 
point of shoots producing inflorescences infect the ovaries as they are 
formed. The mycelium also hibernates in the roots of perennial plants, 
and infects developing shoots as they emerge in the spring. Osner points 
out that the disease may be combated by means of the modified hot-water 
treatment (p. 400), but this would prevent only young plants (seedlings) 
rom becoming infected, for, since he has shown the mycelium to be 
in support of placing the species in Ustilago. This, however, is of little 
significance, since these septa also appear in the probasidia of Tilletia. 
6. Ustilago bromivora (Tulasne) Fischer von Waldheim. (Text-fig. 8, 
and Plate 43, fig. 1.) 
F. v. Waldh., Bull. Soc. Nat. Mosc., vol. 40, p. 252, 1867. 
Ustilago Carbo var. vulgaris d. bromivora Tul., Ann. Sci. Nat., ser. 3, vol. 7, p. 81, 
1847.  Cintractia patagonica Ске. et Mass., Grev., vol. 18, p. 34, 1889. 
Sori in spikelets, often hidden within the lumes, sometimes destroying 
them at the base, at first bullate and somewhat compacted, becoming 
pulverulent, black. 
„Spores globose to shortly elliptical, often polygonal, 8-11 x 7-10 mmm ; 
epispore minutely but densely verrucose, olivaceous or dark reddish-brown, 
1 mmm. thick 
Hosts :— 
Bromus hordeaceus L. In panicles. Herb. No. 442. Blenheim 
(Marlborough), 30m., F. Sisson! 12 Nov., 1920. 
Bromus unioloides Н. B. К. Herb. No. 47. Weraroa (Wellington), 
0m,G.H.C. 11 Dec., 1919. Omahu, Thames Valley (Auck- 
land), W. G. Goodwin! 99 Nov., 1921. Blenheim (Marlborough), 
30m., R. Waters! 91 Nov., 1923. Lincoln (Canterbury), 30 m., 
F. E. Ward! 3 Dec., 1923. с 
Distribution : World-wide. 
The species is fairly abundant on prairie-grass throughout New Zealand. 
In many cases only occasional spikelets may be infected, but as a rule all 
on à panicle are attacked. 
Germination.—In water the spores readily germinate, producing a small 
probasidium, on the apex of which is produced a single elliptical conidium. 
In nutrient solution; according to Brefeld (1883), a two-celled probasidium 
is formed; this produces conidia, which in turn develop a probasidium 
1а. 
- Infection occurs in a manner similar to U. Avenae. MeAlpine (1910) 
states that treating the seed with formalin or copper-sulphate eflectively 
controls this smut 
