field 



aced under belljars with one end of the twig in water were then 

 fected and the growth of the fungus watched, as preliminary to 

 ide on a number of young 



chestnut trees in the propagating houses of the Gar 

 growth commenced in the spring, experiments with dormant trees 

 being carefully avoided. As the preliminary experiments had led 

 me to expect, the actively growing fungus, when transferred 

 from bean stems to the branches of the young trees, attacked them 

 with vigor and soon caused their death by girdling. 



The progress of the disease in infections through natural 



of the Zoological Park and numerous older infected trees through- 

 out Bronx Park. In all of these the fungus was found exceed- 

 ingly active at the beginning of the season of growth, before the 

 opening buds were able to use the large quantity of nourishment 

 at hand. 



The fungus works beneath the cortex in the layers of inner 

 bark and cambium. Its presence is first indicated by the death 

 of the cortex and the change of its color to a pale brown, resemb- 

 ling that of a dead leaf. Later the fruiting pustules push up 

 through the lenticels and give the bark a rough, warty appear- 



lions of minute summer spores emerge from day to day in elon- 

 gated reddish-brown masses, to be disseminated by the wind and 



other 



agencie: 

 i the w 



nated 



changing to yellow with age, 



