192 Tilletia. 



The large coarse projections on the surface of the spore are very pro- 

 nounced, but the fine minute tubercles between are only to be seen by care- 

 ful focussing and fine illumination, or when a spore happens to be crushed 

 they may become plainly visible. 



According to Massee this species appears to be closely allied to T. rau- 

 wenhoffii F. v. W.= T. hold (West.) Rostr.^ but an examination of the speci- 

 men in Sydow's Ustilagineen Exs. 372, shows the decided network of the 

 epispore, which is quite distinct from the warts of T. inolens. 



Germination not known. 



(Plate XLIX.) 



I'riticum. 



56. Tilletia levis Kuehn. 



Kuehn, Hedw. XII., p. 152 (1873). 

 Massee, Bull. Kew., p. 144 (1899). 

 Sacc. Syll. VII., p. 485 (1888). 



Ustilago foetens B. and C. in Grev. III., p. 59 (1874). 

 Tilletia foetens (B. and C.) Trelease, Parasitic Fungi of Wis- 

 consin, p. 35 (1884). 



Sori in ovaries, concealed by the glumes, dark-brown to olivaceous, 

 foetid. 



Spores black in the mass, pale brown to almost colourless in- 

 dividually, globose to elliptic, occasionally somewhat angular, very 

 variable in shape and size, 16-18 /n diam. or 19-25 x 16-17 ^ ; 

 epispore, smooth, 1^-2 /u thick. 

 On Triticum vulgare Vill. — -Wheat. 



Probably in all the States of the CommonAvealth, like T. tritici. This 

 species generally resembles T. tritici, but the spore in addition to being smooth 

 is more irregular in shape and size. Both species may occur in the same ear, 

 but this is easily explained, as a number of spores may infest the one plant ; 

 and if the spores are mixed, then both forms might appear in the same ear. 

 This smooth-spored form is not a mere variation of the species with netted 

 epispore, for it has been used for infecting directly the different species and 

 varieties of wheat, and it remained true to its characteristics. Both species 

 were used for infecting wheat during the past season and invariably remained 

 distinct. 



The smooth-spored form appears to be more common than the other, at 

 least in Victoria. This fungus was first named Ustilago foetens by Berkeley 

 and Curtis in Ravenel's Fungi Carol. Exsicc.X., No. 100, 1860, but no de- 

 scription was published and so the name cannot be accepted. Then Kuehn 

 in 1867 discovered the same form but only published his description in 1873, 

 when he named it as above. 



I have already referred to the amount of loss caused by this smut, and 

 even in the present crop (October, 1909) the yield will be reduced by fully 

 5 bushels per acre in some parts of South Australia. It is also very notice- 

 able that in consecutive plots grown under exactly similar conditions some 

 varieties are much less susceptible than others. Thus Federation and Gluyas 

 were badly affected, while Carmichael's Eclipse showed hardly a sign of it. 



