36 



a mass of separate fibers, which can be pulled out individualh\ This 

 can be seen at the ends of the piece of wood shown in fig. 2 of PL 

 VIII. 



FRXHTING ORGAN. 



The fruiting organ of this fungus is exceedingly common on all the 

 affected trees and has been collected in Maine, New Hampshire, Ver- 

 mont, in the Adirondack forests of New York, and in the forests of 

 Toronto, Quebec, and New Brunswick. It is readily distinguished 

 from allied forms b}" the light red- brown color of the hy menial sur- 

 face, the regular small round pores, and characters of the h^^menial 

 layer shortly to be described. 



The form of the pileus varies exceedingly and i.s almost a distinct 

 one for ever}^ host plant. Hartig, in describing what evidently cor- 

 responds to this fungus, ascribes the difference in form of the pileus 

 and position on the trees to the different amounts of resin or turpen- 

 tine w^hich the wood of the different trees contains. Trametcs j^^nJ^ 

 according to him, forms brackets around the stump of dead branches 

 in the Pine, the Spruce, and the Larch, while on the Fir the sporo- 

 phores may appear at any point on the bark. This is true onh^ to a 

 certain extent for the trees of the Northern woods. Trametes pini is a 

 very common fungus on nearh" all the pines so far seen, and on these 

 trees it always forms very large brackets, which grow, as Hartig says, 

 from old branches. On the Spruce, the Fir, and the Tamarack this does 

 not hold, for on all three of these trees the sporophores form at the 

 ends of old branch stubs and at scattered points on the bark. The 

 resin content of the Spruce is somewhat higher than that of either 

 Tamarack or Fir, and on that account, possibly, the sporophores are 

 more common at the ends of branches. In PI. XII a number of the 

 forms as they are found on the White and Red Spruces are shown. 

 The bark of these trees consists of corky scales which are constanth" 

 being peeled off by newer ones developing beneath. The nnxelium 

 of the fungus, after having penetrated through the sapwood of an 

 affected tree, grows rapidly into the 3^ounger parts of the bark and 

 ultimately appears as small cushions under several of the bark scales. 

 These cushions are bright red-brown and have a velvety margin com- 

 posed of thick- walled h3^ph{e, which rapidly spread out oA^er the adjoin- 

 ing scales, forming a flat sheet (fig. 4). While the growth in a lateral 

 direction is going on, and when the flat sporophore is scarcely one- 

 sixteenth of an inch (about 1.5"^"') in width, some of the central hyphte 

 elongate, leaving small pockets between them which form the pores 

 of the hymenium. The lateral growth may go on for several vears, 

 while at the same time a downward growth of the hyphae which form 

 the walls of the pores brings about an increase in thickness. It ought 

 to be said that this t^^pe of sporophore was found onl}^ on the under 

 sides of fallen logs or branches. When the sporophores form on a 



