134 Minnesota Plant Diseases. 



Bright colored stick-fungi are also allies of these fungi and 

 are very common on dead poplar or cottonwood sticks. On 

 the latter, cushions an eighth to a quarter of an inch in height 

 and breadth, are formed by the fungus and on the surface of 

 the cushion arise the accessory spores in great abundance. 

 After a time these spores cease to form and there is now pro- 

 duced from the same surface, supplanting the accessory spores, 

 the sac-spore capsules of the fungus, which are again pear- 

 shaped cavities with pore-like opening to the exterior. The 

 sac-spores are -short and rounded at the ends and two-celled. 

 Some of these fungi are wound-parasites attacking orchards 

 and timber trees through storm or hail-wounds, etc. They are 

 sometimes known as red knot. In some of these fungi still 

 other kinds of spores and spore-bearing organs are encountered. 



