170 DR. ETHEL M. DOIDGE 



Perisporiaceae. 



Perthecia spherical. 



A. Spores 2-eelled. 



a. Mycelium conspicuous. 



1, Perithecium containing one ascus Balladyna. 



2. Perithecium containing several asci. 

 0. Spores colourless. 



X. Perithecia smooth D inter osporium, 



XX. Perithecia with set.'B Dimeriella, 



oo. Spores brown, 



X. Perithecia smooth Dimerium. 



XX. Perithecia with setse Phaeodimeriella, 



h. Mycelium none or poorly developed Parodiella. 



B. Spores 3 or more celled. 



1. Spores colourless Zukalia, 



2. Spores brown Meliola. 



The genus Meliola is the most richly represented in 

 South Africa, some fifty species have been described up 

 to the present. Within the genus the chief points to be 

 studied are the form of the hypho podia, which may be 

 rounded as in McMola glabra (Fig. 3) or more or less ela- 

 borately lobed (Fig. 2 A) ; the presence or absence of 

 setae is also to be noted, and if present whether they are 

 erect or curved, simple or branched. The tips of the 

 setae should be carefully studied , as some species are 

 characterised by setne forked or toothed at the tip (Fig. 

 2 C). 



Another important point is the number of cells in the 

 spore and the dimensions of the spores, perithecia and 

 vegetative organs, and for this pui'i)Ose a micrometer 

 ocular will be required if it is proposed to study the fungi 

 in detail and to determine species. Most collectors will 

 probably be content to assign a fungus to its genus and 

 send their specimens to the National Herbarium, Pre- 

 toria, for the determination of the species. 



