180 FUNGI IMPERFECTI 



milk and cheese. It can produce a feeble alcoholic fermentation 

 in saccharine liquids. Thrush or aphthae (0. albicans) appears as 

 white spots in the mouths of children. Several similar Oidium- 

 forms are parasites on the skin and hair of human beings, and 

 produce skin diseases, such as scurvy (0. schoenleinii) and ring- 

 worm (0. tonsurans). 



3. Mycorrhiza. Certain Fungi, which have been found on 

 the roots of man}' trees and heath-plants, particularly Cupuliferse 

 and Ericaceae, consist of septate hyphse, and belong partly to the 

 Hymenomycetes, partly to the Gasteromycetes. It has been shown 

 that they enter into a symbiotic relationship with the roots of 

 higher plants, producing a condition known as Mycorrhiza. 



