150 



Mycologia 



an open trough-like rupture with the epidermis rolled back on 

 either side. It is probable that the period from infection to for- 

 mation of mature fruiting bodies, in the majority of cases, is 

 approximately one year, varying somewhat with weather con- 

 ditions: there are apparently many cases in which this period is 

 nearly two years and possibly even more. This disease is very 

 prevalent in the Adirondack region and apparently occurs though- 

 out the range of the balsam fir. It has not yet been found in 

 nurseries, since its host is not much grown therein. 



Peridermium fructigenum Arthur 



Spores of Peridermium fructigenum from cones of Tsuga 

 canadensis (L.) Carr., which had been collected in Connecticut 

 two days before, were used to inoculate leaves of the following 

 species of Rhododendron and Kalmia. Rhododendron arbores- 

 cens (Pursh.) Torrey, R. viscosum (L.) Torrey, R. nudiflorum 

 (L.) Torrey, R. canescens (Michx.) G. Don., R. calendulaceum 

 (Michx.) Torrey, R. canadense (L.) B.S.P., R. maximum L., 

 R. catawhiense Michx., Kalmia latifolia L., and K, angustifolia 

 L. The inoculated plants were in a greenhouse at Washington 

 and had their leaves further developed than would have been 

 the case out of 4oors in Connecticut. This may have had an 

 effect upon the results secured. In no case did infection occur, 

 although the inoculations were made with and without wounds 

 upon each species. 



Lightning 



While engaged in reconnaisance for the chestnut blight in 

 Maryland, the past season, the writer time and time again 

 examined chestnut trees which at a distance apparently were 

 affected by blight, but which were killed, either completely or 

 partially by lightning. Occasionally groups of trees standing 

 close together were partially killed about some central tree which 

 usually was entirely dead. More often only single trees were 

 struck. The frequency of occurrence of such cases soon became 

 very noticeable, especially the latter part of the summer. There 

 must have been an average of three or four trees per square 

 mile which were killed or badly crippled by lightning in a single 

 season in the territory examined by the writer. 



