146 



PLANT DISEASES 



in a low, damp situation. The ascopbore is i to 2 lines 

 across, saucer-shaped, without a stem, but attached by a 

 narrow point, externally white and downy, inside or 

 hymenium orange-red. Usually occurring in considerable 

 numbers on the diseased spots. 



The fungus is a wound-parasite, its spores entering the 

 tissue through wounds caused by insects, hailstones, and 



Fig, 30. — Dasyscypha. calycina. i, portion of a larch 

 branch diseased ; ■^, two fungi, slightly mag. ; 3, an 

 ascus containing eight ascospores, also two para- 

 physes, X300. 



more especially by branches being more or less split from 

 the trunk by snow. The first indication of disease is the 

 yellowing and wilting of the needles. If the base of a 

 branch bearing such leaves is examined, a mass of resin 

 will be found oozing to the surface through irregular fissures 

 in the bark. By degrees the bark is entirely destroyed 



