120 



Mycologia 



apples^ plums, apricots and especially mulberries in Kashmir, 

 India. It is found in the trunk, but also attacks the larger 

 branches. Butler finds that the fungus enters branch scars where 

 heart-wood is exposed, and says : "The tissues are little by little 

 destroyed from within out, becoming soft, spongy and yellowish 

 white. The trunk may be almost completely hollowed, but often 

 a ring of still living wood is left which is sufficient to keep the 

 crown green." In most cases the trees thus weakened are blown 

 over before they are killed out entirely. This mode of action corre- 

 sponds closely with the condition of affairs in the oak above 

 described. 



3. Pyro poly poms Everhartii (Ellis & Gall.) Murr. — A huge 

 pin oak (Quercus palustris Muench.) at Englewood Heights, N. 

 J., has attracted a good deal of attention for a number of years 

 on account of numerous gnarly swellings which appear toward 

 the base of the trunk. Each swelling was found to contain in 

 some part of it young or old fruiting bodies of this fungus — also 

 known as Fomes Everhartii (Ellis and Gall.) von Schrenk and 

 Spauld. — indicating that the organism was the cause of the dis- 

 turbance (Plate 10, fig. i). The fungus had grown in the trunk 

 for a long period of years, if one were to judge from the thick- 

 ness of the bark and wood of which the swellings were composed. 



That this species has parasitic habits has already been pointed 

 out by Von Schrenk and Spaulding,^^ who found it of common 

 occurrence on living black jack oak {Quercus marilandica 

 Muench.) and determined that the mycelium of the fungus "was 

 capable of growing into the sapwood of the living tree." Hedg- 

 cock^^ finds it causing a very destructive heart rot in a large num- 

 ber of species of oak in the United States and states that it is the 

 cause of the most common and destructive heart rot of walnut, 

 especially Jiiglans rupestris, although /. nigra and /. calif ornica 

 are frequently attacked. /. cinerea is apparently rarely attacked. 

 Other hosts are Prosopis juli flora (Swartz) deC. the mesquite, 

 Fagus atropunicea (Marsh.) Sudw. the beech, Betula papyrifera 



18 Von Schrenk, H., and Spaulding, P. Diseases of deciduous forest trees. 

 U. S. Dept. Agr. Bur. Plant Ind. Bui. 149, p. 48. 1909- 



i» Hedgcock, G. G. L. c. pp. 74, 75. I 



I 



