302 TWO AUSTRALIAN FUNGI, 



Uncinula australiaxa, n.sp. — Australian Uncmiiia. 



(Plate xxiii., figs. 5-9). 



On twigs and leaves and covering entire inflorescence with a 

 greyish-fawn, firm, powdery mass, usually studded over with the 

 minute, black perithecia. 



Conidial stage — ^Hyphaj veiy slender, colourless, septate, 

 branched, often only 1 ^ broad and up to 2\ fx. Conidia in chains, 

 colourless, oblong, with finely granular contents, constant in size, 

 30 X 13-14 fx] (stained golden brown by potassium-iodide-iodine). 



Perithecial stage — Perithecia intermixed with the conidia, 

 densely gregarious, black, punctiform, dark brown by transmitted 

 light, globular, with bulging boss-like polygonal markings on wall, 

 112-130 fjL diam.; appendages rigid, radiating, occasionally forked, 

 moderately numerous, hyaline, but basal portion brown, some- 

 times slightly swollen and marked off by a septum, rather longer 

 than diameter of perithecium, average breadth 6 /x, apex 

 involute. 



Mature asci and sporidia not found. Immature asci (4) 

 colourless, roughly pear-shaped, with finely granular contents, 

 except at tapering end, 28 x 22 /x. 



Immature sporidium colourless, elliptical, with finely granular 

 contents, 13 x 10 /x. 



On Lagerstrieniia ovali/olia, Teys. ; February-May; Botanic 

 Gardens, Sydney. Received from Mr. J. H. Maiden, but first 

 observed by his assistant, Mr. A Grant. 



Although the perithecia are very numerous, mature asci were 

 not distinctly found, and this is not because they have already 

 burst and shed their spores, but that they are not yet formed, the 

 contents of the perithecium usually consisting of formative 

 material and oil globules. In apparently older perithecia, the 

 contents are of a bright yellow colour. 



Fresh specimens were obtained in both February and May, 

 and the perithecia do not seem to mature their asci. The append- 

 ages were usually simple, but forking occasionally occurred. 



