29 



III the last stages of decay the fissures are very numerous, each filled 

 with a solid felt of white mycelium. The felts extending in radial 

 lines join those extending in tangential lines here and there, and they 

 hold in place the wood which would otherwise have fallen to pieces 

 long Ijcfore. In a live tree the heartwood is attacked first, and grad- 

 ual 1}^ the decay spreads to the sap wood. In the latter the browning 

 of the wood is more marked, owing to its lighter color. Nothing- 

 positive can be stated at present as to the rapidity Avith which the 

 decay brought about by this fungus proceeds. It appears to be very 

 rapid, for trees blown down some two years before were found in an 

 advanced stage of decomposition, with sporophores forming on their 

 trunks at various places. 



FRUITING ORGAN. 



The sporophores of this fungus are very large and conspicuous, and 

 arc formed on logs during spring and summer, often many together on 

 the same log. The form of the pileus is exceedingly variable (PL V). 

 It is entirely resupinate when growing on the lower side of an over- 

 turned log (PL IX, fig. 6). In such a case there is no upper surface 

 for several years. After three or four years the edge extends out 

 beyond the curved surface of the log, and a narrow surface is exposed. 

 Usually the pileus forms a distinct bracket on the side of a standing 

 trunk or log. This bracket is sometimes hoof -shaped, then again very 

 much extended. In size it varies from an inch to a foot (2.5 to 30''"') 

 in width, or even more in extreme cases. The average specimen is 4 

 to 6 inches (10 to 15''°') wide. The upper surface of the bracket slopes 

 toward the margin, and is divided into a number of regular divisions 

 or lobes, which correspond evidently to periods of growth (PL V). 

 The lobes are smooth and dark red-brown when old. The youngest lobe 

 is bright red, shading into a pale yellow at the very edge of the pileus. 

 In many specimens the upper surface is almost black, and some of the 

 lobes shine as if varnished. The number of lobes varies with the age of 

 the specimen; one of the oldest found had fourteen. It has not been 

 determined whether these lobes represent annual increments of growth, 

 so it is not possible to say how old any of these large sporophores may 

 be. The mass of the pileus is extremely hard and woody, and shows 

 division into a number of zones (PL IX, figs. 5, 6, 7), which are always 

 greater in number than the lobes showing at the top. The hymenium 

 is a pale yellow, very smooth, and assumes a watery appearance when 

 bruised. It is very rarely perfect, as many insects are constantly at 

 work eating away the tissue. The outer edge of the lower surface of 

 the pileus is raised, forming a distinct ridge. At the inner edge of 

 this ridge the formation of the tubes of the hymenium begins. This 

 ridge is continuous around the whole lower surface and forms a char- 

 acter which itj very constant. In young individuals it is wider than 



