MILDEWS, RUSTS AND SMUTS 
195 
The genus is widely distributed throughout the world, 
whereas the species are mostly restricted in their range, 
each being limited to a portion of one Continent, with the 
exception of those species parasitic on cultivated cereals, 
which have been distributed by artihcial means. 
All the British species grow on grasses, 
A. Spore-mass produced in the ovary. 
Tilletia caries. Tub 
Spore-mass produced in the ovary, blackish, with a 
tinge of olive, foetid ; spores subglobose, brown, 17—22 [i, 
border i—1.5 p. broad, not paler, epispore covered with a 
network of rather large mesh of variable size, averaging 
3—3.5 p across. 
Syn. Tilletia tritici, Wint. ; Plowr., Ured., p. 283. 
Uredo caries, D.C. 
On wheat— Triticum vulgare, T. spelta, T. monococcum. 
Europe generally, Algeria, Queensland, Victoria, United 
States, Chili. 
Tilletia rauwenhoffi, Fischer de Waldh. 
Spore-mass produced in the ovary, blackish ; spores 
almost constantly globose, olive-brown, 25—-30 p, epispore 
with a large irregularly hexagonal network, mesh averaging 
3—^4 p across. 
Syn, Polyactis hold, Westend. 
On Holcus lanatus and H. mollis. 
Readily distinguished by the large size of the network 
of the epispore, only 4—6 areolae being present on a 
hemisphere. 
The hrst recorded British specimens were collected by the 
late Mr. T. Soppitt, at the Doncaster Meeting of the York¬ 
shire Naturalists’ Fungus Foray, .1891. 
Tilletia laevis, Kuhn. 
Spore-mass produced in the ovary, deep brown with an 
olive tinge, very foetid ; spores subglobose or elliptic, 
variable in size and form, 17—21 p, or 15—26 X 10—15 p, 
wall about 2 p thick, pale brown or almost cream-colour, 
wall smooth. 
Syn. Ustilago foetens. Berk, and Curt. 
On wheat— Triticum vulgare. 
The spore-mass, more especially when rubbed, has a 
smell resembling rotten fish. 
Europe generally. United States, and Victoria. 
Tilletia separata, Kunze. 
Spore-mass formed in the ovary, blackish-brown, foetid ; 
