156 Ustilago. 



On Triodia mitchelli Beiitli. 

 Queensland — (Bailey). 



Bailey kindly sent me a specimen from his Herbarium, and in an accom- 

 panying note remarked — " I obtained it many years ago and sent samples 

 to Berkeley and Broome, who at first named it Ustilago carbo TuL, after- 

 wards changing it to U. secjetum Berk. 



In the original description of this species on Bouteloua ciUata Grisel. from 

 the Argentine, the spores are given as 11-15 x 8-13 i-i and said to be some- 

 what punctate. Clinton also records it on Triodia jmlcheUa H. B. and K. 

 from Arizona, and speaks of the spores as rather obscurely cchinulate, but 

 in the Queensland specimens they are prominently so. 



This is a very variable species, and in the absence of sufficient material 

 on Triodia for fuller investigation, this particular smut will be retained here 

 for the present. 



(Plate XXXI.) 



Polygonum. 



12. Ustilago hydropiperis var. columellifera Tul. 



Berkeley. Journ. Linn. Soc. London XIII., p. 171 (1872). 

 Cooke, Handb. Austr. Fung. p. 327 (1892). 

 8ori produced in the ovaries, the solitary ovule of each being completely 

 transformed and replaced by the fungus ; the outer portion sharply 

 defined and compact ; composed of spore-like barren cells, forms 

 a distinct urn-shaped spore-receptacle, open at the top and with 

 reflected margin, the central por<-ion projects as a dark-j)urplish 

 body, the so-called columella, up to 4 mm. long, hollow in the centre, 

 composed of similar cells to that of the wall, and coated with a dense 

 mass of the violet-coloured spores. 



Spores purplish, oblong to ovoid, but generally subspherical, 

 very finely echinulate, 10-13 n diam. or 11-12 x 8 / . 

 On Polygonum minus Huds. 



Tasmania — Near Launceston, March, 1893 (Rodway). 

 On Polygonum sp. 



Queensland — (Bailey). 

 In the transverse section of this fungus (PI. XXXII.) towards the base of 

 an affected ovary, the wall of the ovary is seen detached quite unaffected 

 by the fungus. Inside, the tissue of the ovule has been entirely replaced 

 by fungus cells, the centre being hollow. The inner colourless cells surround- 

 ing the cavity are similar to those on the outer side, and the dark-purple ring 

 between consists of the spores. The colourless cells readily separate from each 

 other and are subspherical, differing from the spores in having generally a 

 thicker wall, which is not echinulate. The spores gradually merge into them 

 on either side, and they are, in all probability, immature spores. When 

 fully developed, the outer wall splits at the top, forming an urn-shaped recep- 

 tacle, while the central portion elongates as the columella carrying some of 

 the spores with it. 



The species of Avhich the above is considered a variety was made the type 

 of a new genus by I)e Bary, and named by him Sphacelotheca mainly on account 

 of the distinct spore-receptacle formed of fungus cells, but also because of 

 the central columella and the differentiation of the spore-layer into sterile 



