52 THE AMERICAN BOTANIST. 



mycelium may be traced throughout all their decaying parts. 

 It is composed of countless numbers of fine hair-like processes 

 with tiny outlets which take up such material as is conducive 

 to the growth of the fungus. 



In order to grow the fungus must have a large per cent of 

 moisture, and often, after a rainy spell, one may find such 

 growths on stumps and fence rails in high, dry places, where 

 before it gave no evidence of its existence. The mycelium was 

 there, however, but in a dormant state until the rain nourished 

 it into action. 



The genus, which perhaps is represented by the most spec- 

 ies of wood destroying fungi, is the Polyporiis. A few 

 of this genus are reported as edible but the greater number are 

 too corky and tough, when mature, to be fit for food. In the 

 species of this genus the tubes are not separable from each oth- 

 er. One of the most common is Poly poms hirsiitiis, so called 

 from the nimierous short stiff hairs which cover the cap, and 

 give it a velvety appearance. It occurs most abundantly on 

 wood of fallen trees but in some cases I have found it on stand- 

 ing trees also. It is usually a sessile species but one may often 

 find it in umbilicate form when it is supported by a short cen- 

 tral stem. The cap is grayish or brown, often zoned with light- 

 er or darker shades. The fruiting surface is at first yellowish, 

 then brown, but exceptions to this rule are frequently met with 

 for I have found plants, comparatively young, whose under 

 surface was as dark colored as many of the older ones. The 

 tubes are very regular in arrangement and may be seen very 

 readily with the aid of a pocket lens. In fact it adds greatly to 

 the interest of the obsener if he possesses a good lens, as it 

 brings to light many hidden and interesting facts. A damp 

 wood makes an excellent place for the growth of this fungus, 

 especially after a rainy spell, when hundreds of young plants 

 may be found on old brush heaps and dead branches. It is not 

 found to any great extent in high dry woods. 



