the plant produces a secondary abortive pileus, and that the fertile por- 

 tion falls away, while the cup persists through the winter, but does not 

 produce a fertile portion the following season. 



Polystictus conchifer grows only on the elm and only in the United 

 States and Canada, as far as I know. It was named by Schwc-initz the 

 "shell-bearing," and he likened the sterile cup to a shell. I le also called 

 a species Polystictus virgineus, which, according to specimens in his 

 herbarium, is the same as conchifer. Cooke used the name virgineus 

 and tried to sink the name conchifer, but it was not a success, as con- 

 ctiifer is too good a name to be put aside. Besides there is some doubt 

 as to virgineus, for, while there is no doubt the plant in Schweinitz's 

 herbarium as virgineus is conchifer, it never takes either the shape or 

 color as shown in a figure that Schweinitz gave of it. Either the figure 

 is very poor of the plant, or represents something else. 



FOMES GRAVEOLEXS (Fig. 367). This is another curious 

 plant that was named by Schweinitz, and it is unique in the fact that 

 there is no other similar plant known in any portion of the world. 22 



Fig. 368. 



Section of Fomes gravcolens. 



It is a true Fomes, evidently of slow growth, and the densely imbricate 

 pilei grow from a globose, woody core. Its manner of growth is 

 plainly shown in our section (Fig. 368). The context 



a In our text-books it is placed in a section Merisma, with a half dozen other., none of 

 which have the slightest resemblance to it in their manner of growth. 



43 



