Soros pari uin. i8r 



Setaria. 

 40. Sorosporium setariae Mc.Vlp. 



Sori destroying tlie entire inflorescence and converting the ovaries into 

 a black powdery mass, or they may only affect one side of the in- 

 florescence and sometimes the base, while the upper part is sound. 



Spore-balls dark-brown, variously shaped, globose to oval, oblong 

 to angular, consisting of numerous spores, varying in length from 

 60 to 160 //. 



Spores brown to olivaceous, globose, ellipsoid to angular, smooth, 

 10-12 ^i diam. or 10-13 x 7-10 /.. 

 On Setaria glauca Beauv. 



Queensland — Near Cloncurry, May, 1909 (Eobinson). 

 This is the first Sorosporium found on this genus. A cross-section of 

 the ovary shows that the spore-balls are developed around the vascvdar 

 bundles, the youngest being nearest the bundle. Adjoining each bundle 

 may be seen the gelatinized hyphae concentrically arranged and enclosing 

 minute colourless points which afterwards become the spore-balls, and to- 

 wards the circumference are the dark-brown spore-masses fully mature. 

 There is also a central core of tissue around which the spore-balls are de- 

 veloped last of all, and the outer tissue of the ovary finally ruptures to allow 

 of the escape of the powdery spore-masses. 



Germination. — The spores do not germinate readily. After floating on 

 water in a watch-glass for seven days, a few had put forth a colourless con- 

 tinuous germinal tube, usually without conidia, but, in some cases, with lateral 

 and terminal conidia. The conidia were minute, about 3 ^i long. 



(Plate LIV.) 



Schoenus. 

 41. Sorosporium solidum (Berk.) Mc Alp. 



Ustikujo soUda Berk., Fl. Tasm. II., p. 270, (1860). 

 TJrocystis solida Fischer von Waldheim, Apercu syst. Ust, 

 p. 38 (1877). 

 Sori in ovaries, black, compact, globose, shot-like. 



Spore-balls subglobose to oblong or irregular, composed of 30 or 

 more spores all similarly coloured when mature and somewhat 

 firmly united, 50-70 ^t long. 



Spores dark-brown, smooth, with firm epispore, spherical to 

 sub-spherical, elliptical or polygonal, 20-24 /.■ long. 

 On Schoenus imherhis R. Br. 



Victoria— Cheltenham (Mrs. Martin). Nov., 1906 (Robinson), 

 Tasmania — Penquite, Dec, 1845 (Gunn.) 

 On Schoenus apogon Roem. and Schult. 



Victoria — Dimboola, Nov., 1892 (Reader). 



Tasmania — Hobart, Nov., 1894 (Rodway). 



F, von Waldheim, who recorded this as a Urocystis, speaks of the 



glomerulcs of spores as having rarely three to four peripheral vesicles, 



but the examination of a large number of spores failed to reveal any distinct 



peripheral cells. But there are hyaline protuberances attached to the cells 



