81 



The remaining portions thc^n form separate centers of growth, which 

 gradually spread over the dead portion and unite, after several years 

 perhaps, complete!}^ covering the dead part. A view of such a pileus 

 is shown on PL IX, fig. 4; several areas have already joined, forming 

 a larger one, and a number of small centers are evident. 



The spores begin to be discharged in July. Growth of the lower 

 side of the pileus takes place at the same time. Black cloths were 

 pinned to the under side in June and b}^ the end of August large por- 

 tions of them were found completely overgrown Avith hyphte, and 

 pores were beginning to form on the under side of the cloth. While 

 the growing season lasts drops of a glistening yellow liquid are con- 

 stantly being discharged from the hymenium. It is of interest to note 

 here that the secretion of these drops was noticed b}^ Fries in a 

 description of this fungus.^ Several cubic centimeters of these were 

 collected and were found to hold in solution melezitose, the same 

 sugar discharged from the sporophores of Polyporus scTiioeinitzii. As 

 insects, particularly small boring beetles, eat the hymenium with 

 great avidity, it is possible that the sugar may serve to attract these 

 insects to the sporophores, causing them to carry the spores to unin- 

 fected trees. 



TRAMETES PINI (Brot. ) Fr. forma ABIETIS Karst. 



Polyporus piceinus Peck. 

 Polyporus abietis Karsten. 



OCCURRENCE. 



This fungus is ver}^ common in the forests of the New England 

 States, and occurs northward into Canada and Newfoundland. The 

 writer found it common on the Spruces and Firs in the Adirondack 

 forests. It grows on nearly all the conifers and has been found by the 

 writer on the White Pine [Pimis strobus)^ the Red Spruce {Plcea 

 rubens), the White Spruce {Picea canadensis)^ the Hemlock {Tsuga 

 canadensis)^ the Larch, or Tamarack {Larix laricina), and the Fir 

 (Abies balsamea). It attacks living trees after they haA'e reached such 

 a size that they form heartwood, and honej^combs the wood in such a 

 way that it appears filled with small holes, many of which are coated 

 with a shining white lining. The changes which are brought about in 

 the wood are different somewhat for the different kinds of trees and will 

 be described separately. Of the six trees the Tamarack seems to be 

 the most readily attacked. A greater per cent of the older trees of 

 this species were found affected than of the other five. The Spruces 

 came next, and the Balsam Fir last. 



The fungus enters the trees through the stubs of In'okeii ))ranches 



^ Fries, Elias. Epicrisis Syst. Myc. 468. 1836-1838. 



