OOSPORA 457 



SEPTOGLOEUM (Sacc.) 



Spore-masses minute, produced beneath the epidermis, 

 sometimes erumpent, pallid; conidia oblong, 2-many-septate, 

 hyaline. 



Resembling G/oeosporium, but with septate conidia. 



Maple blight. Hartig states that in the neighbourhood 

 of Munich the branches of Acer campestre are often killed off 

 before the young shoots develop in the spring by a fungus called 

 Septogloeum Hartigianicm (Sacc). In the middle and lower 

 parts of the crown, more especially, often more than half of 

 the shoots of the previous year are killed. As a rule only 

 young shoots are attacked, infection taking place while the 

 epidermis is still tender. When spores alight on the surface 

 of such shoots, they germinate within a few hours, the germ- 

 tubes piercing the epidermis and gradually extending for a 

 distance of two to four inches, passing along the medullary 

 rays and into the vessels. At a later stage the fungus forms 

 cushion-like masses of fruiting bodies under the epidermis, 

 which becomes ruptured at these points. Shoots that are 

 attacked do not die the same year, and show no external 

 evidence of the disease during the autumn. 



Spore-beds erumpent, elongated, gregarious, 1-2 mm. long, 

 greyish-green, bordered by the torn epidermis. The crowded, 

 cylindrical conidiophores spring from a colourless stroma, and 

 each bears at its summit an ovate-oblong, 1-3-septate, most 

 frequently 2-septate subhyaline conidium, 24-36 X 10-12 \i. 



Hartig states that infection takes place in May or June, by 

 conidia washed by rain from the higher diseased branches on 

 to the young shoots situated lower down. Dead shoots 

 should be removed from the crown during the winter. 



Hartig, Forstl. Nat. Zeitschr., Aug. 1892. 



HYPHOMYCETES 



* Spores continuous 



OOSPORA (Wallr.) 



Tufts delicate, effused or pulvinate, lax or rather compact, 

 fertile hyphae, short, slender, simple, or sparingly branched ; 

 conidia produced in chains, globose or elliptical, hyaline or 

 clear coloured. 



