PERISPORIALES 



207 



through the stomata, and there forms numerous haustoria; these are 

 reminiscent of the sinkers of Phyllactinia and are called stomatopodia ; 

 their development corresponds to that shown in Fig. 134 for Parodiopsis; 

 only in Balladyna the haustoria are coralloid and almost fill the host cell, 

 somewhat as depicted in Fig. 203, 3 for Asterina Usterii (Raciborski, 1900; 

 Arnaud, 1918). 



The perithecia arise from the clavate terminal cells of the branches 

 of the aerial mycelium. In youth they are light brown, spherical; in 

 age, brown, or black and ovoid. Their rind consists of a single layer of 

 brownish, polygonal cells which at maturity become a greenish, almost 

 hyaline slimy mass (Fig. 131, 2). The interior of the perithecium con- 

 tains one, rarely two asci, each with eight dark, two-celled spores. Bal- 

 ladyna appears to hold a place among its relatives similar to that of 



Fig. 131. — Balladyna Gardeniae. 1. Fungus mat showing hyphopodia, H, on the lower 

 surface of a leaf, with setae, B, and young fundaments of fructifications, P. 2. Mature 

 fructification. (X 250; after Arnaud, 1918.) 



Sphaerotheca among the Erysiphaceae, in that neighboring forms, e.g., 

 the Javan Alina J asmini, possess polyascous perithecia. 



Meliola (Gaillard, 1892; Beeli, 1920; Doidge, 1920a, 1921; Ryan, 1926; 

 Stevens, 1927) includes at present mostly tropical species (about 300), 

 which form brown radiating mats on the under sides of leaves and fruits, 

 rarely on young twigs. The asterinoid habit is already so marked that 

 they are often considered epiphytes; in the more carefully investigated 

 species, however, as Balladyna and the Erysiphaceae, they are ectopara- 

 sitic, sending knob-like haustoria into the epidermal cells and the tissue 

 beneath (Maire, 1908; Doidge, 1921). As plant parasites they do not 

 cause serious injury; however, some of them, as Meliola Camelliae and M. 

 Penzigii on oranges and other citrus species, considerably diminish the 

 value of the wares. 



The hyphae are brownish black to brownish red; the growing parts 

 and the parts which lie next the substrate are finer, lighter and thinner 



