J910-1911.] Notes on Parasitic A scomycetes, 3 39 



E. Martii L^v., which is often abundant on various legum- 

 inous plants, especially zigzag-clover, yellow meadow-vetch- 

 ling, and garden pea, on the leaves of which it produces a con- 

 spicuous white mycelium studded over with minute black 

 perithecia ; 



E. umlelliferarum De Bary, which occurs on leaves of vari- 

 ous Umbelliferae, especially those of cow-parsnip ; 



E. graminis DC, which is common in summer in its 

 conidial state (Oidium monilioides Link) as mildew on the 

 leaves of various grasses, but produces its perithecia somewhat 

 sparingly ; 



E. communis (Wallr.) Fr., which occurs on leaves of creep- 

 ing-buttercup and various other plants ; and 



E. cichoracearum DC, which is common on leaves of bur- 

 dock, thistle, comfrey, plantain, and certain other herbaceous 

 plants. 



Turning now to the second group of the Perisporiacese — viz., 

 the Perisporiese, or species furnished with a blackish mycelium 

 — it may be noted that these are much less injurious to their 

 respective host-plants than are the Erysiphese, or species fur- 

 nished with a white mycelium. Several of the Perisporieae, 

 indeed, are believed not to be truly parasitic, but to be attracted 

 by honey-dew or other secretion deposited on leaves by insects. 

 The mycelium of such species forms an agglutinated coat of 

 dark- coloured threads, which often breaks from the leaf and 

 peels off in fragments. In this group three genera may be 

 noted — viz., Meliola, Asterina, and Capnodium. 



Meliola is represented by M. Niessleana Wint., which is a 

 recent addition to our Scottish fungus-flora, having been first 

 recorded as British from specimens gathered in Perthshire in 

 1907. It has also, however, been found in Ayrshire, and is 

 likely to occur in hilly districts within the Forth Area. It 

 grows on the leaves, and less frequently on the stems, of cow- 

 berry ( Vaccinium Vitis-Idcea), which it coats with rounded or 

 irregular spots of blackish mycelium ; and on the mycelium are 

 produced globose black perithecia surrounded by rigid setae. 

 Each ascus contains from two to four dark-brown triseptate 

 spores. This is a very pretty and interesting species, which 

 should be looked for wherever the cowberry grows in abund- 

 ance. It may be further noted that the Perthshire specimens 



