Ustilago. i6i 



laterally or even direct from the spore as a slender, elongated, more or less 

 wavy filament, which may reach a length of 200-300 p. At first it is non- 

 septate, but afterwards becomes septate and even branched. The spore 

 may give rise to two promycelia, one being usually shorter than the other. 



Spores immersed in liquid do not germinate as readily as those floating 

 on the surface. Thus, after 18 hours on one occasion, the spores in the water 

 had failed to germinate, while by simply altering the focus and examining 

 the spores on the surface, they were all found, with very few exceptions, 

 to have germinated. This germination at the surface was in various stages. 

 Some had just put forth a short, slender, simple promycelium ; others had 

 produced an elongated, septate promycelium ; and still others had put forth 

 slender branches from the segments of the promycelium. In some cases the 

 septate promycelium tapered out into a long wavy filament, and when the 

 liquid began to dry up, these filaments became exceedingly long and exceed- 

 ingly wavy, and ultimately became detached. 



(Plates XVIIL, XXXI., LIII.) 



Stenotaphnim. 



16. Ustilago stenotaphri McAlp. 



McAlpine, Agr. Gaz., New South Wales, Vol. VI., p. 758 (1895). 

 Sacc. Syll. XIV., p. 415 (1899). 

 Sori on stem and leaves, giving them a blackened appearance as if charred, 

 compact, completely surrounding part attacked, which is usually the 

 younger growth. 



Spores dark-brown, subglobose to ellipsoid or irregular, smooth, 

 16-17 X 10-13 p. 

 On Stenotaphrum glabrum Tr'in. (Buffalo grass) = S. americanum Schrank. 



Victoria— Kew, June, 1890 (Ralph). 

 There is another smut affecting Buffalo-grass, but it occurs in the sjjike- 

 lets, and the spores are only 5-9 /< in length. This is U. affinis Ell. and Ev., 

 but it was also named U. stenotaphri by P. Hennings (1898) and Massee 

 (1899) respectively. The host-plant is frequently regarded as an introduced 

 grass, but it is a true native of Australia, as well as of America. 



(Plate XXXII.) 



Amphipogon , Xeurachtie. 

 17. Ustilago tepperi Ludw. 



Ludwig, Bot. Centr. 341 (1889). 

 Sori in stem and flowers, black, powdery, destroying the parts affected. 

 Spores globose or shortly ellipsoid, brown, papillate or rather 

 aculeate, 12-17 /.i diam. 

 On Amphipocjon strictus R. Br. and Neurachne ahpecuroides R. Br. 



South Australia — Torrens Gorge and Highbury Scrub (Tepper). 

 I could not obtain a specimen of this smut, and have never met with a 

 smut of any kind on either of these hosts. 



