Shade Tkee and Timber Destroying Fungi. 



229 



openings in some specimens, or irregular, elongated and sinuous 

 pores in other specimens, resembling the pores of Dmdalea. But 

 they are evidently sunk in the substance of the cap and therefore 

 lack the essential character of that genus. The walls of the pores 

 are thin, and the edges often irregular and jagged. 



There are two cases of its 

 occurrence on living conif- 

 erous trees which I liave 

 carefully studied. One case 

 is that of a hemlock spruce 

 [Tsuga canadensis). The 

 other is that of a red spruce 

 {Picea rubra), the common 

 timber spruce of the Adi- 

 rondack region. 



The hemlock spruce was 

 a large tree, 60 cm. (2 ft.) in 

 diameter, on a steep slope in 

 one of the deep gorges (Fall 

 Creek) at Ithaca, K. Y. 



This example was ob- 

 served in the autumn of 

 1899. The fruit body of 

 the funo-us was situated at 

 a laro;e wound on the trunk 

 near the base. It consisted 

 of several caps closely 

 joined at their origin from 

 the trunk of the tree. This is well shown in the several photo- 

 graphs. A section through the entire fruit body (Fig. 57) shows 

 the radiating lines formed by the general direction of the mycelium 

 in the caps from their common origin in the tree trunk. 



One of the photographs gives us a clue to the manner in which 

 the mycelium of the fungus entered this particular tree. The log, 

 lying in the foreground, close by the trunk of the affected tree, tells 

 the tale. This tree in its descent, years ago, struck the slightly pro- 

 jecting base of the standing hemlock, and knocked off a large area 



::.':4^m 



59.- 



Polyiwrus horealis, Ilymenium with 

 rounded pores. 



