distinct. A fragrant form is called Polyporus fragrans. The same form oc- 

 curs in Europe, but there it has not been thought worthy of a separate name. 



Polyporus arcularius. A very common plant around Cincinnati in the 

 spring. 



Polyporus Berkeley!. The largest polyporus we have, usually at the 

 base of oak-trees. It does not grow in Europe. 



Polyporus betulinus. In birch regions a frequent plant and well named, 

 for I think it is confined to the birch. 



Polyporus brumal is. This plant reaches me very often from correspond- 

 ents, but I have never collected it at Cincinnati. 



Polyporus elegans. Frequent in northern stations (not at Cincinnati). 



Polyporus giganteus. As generally known in the United States, though 

 now disputed. My American plants have been so referred in Europe. 



Polyporus gilvus. Very common and somewhat changeable. Wide- 

 spread in the world,' and tropical forms have" received many names. 

 Strange to say, it is not surely known from Europe, though Fries claims to 

 recognize it as one of Sowerby's pictures. 



Polyporus intybaceus. It has always been a puzzle to me whether this 

 is Polyporus intybaceus or Polyporus frondosus, or whether these two are 

 the same or different. Atkinson gives a good photograph of it under the 

 former name. It is Polyporus anax of Morgan's flora, but Polyporus anax, 

 the type, is Polyporus Berkeleyi. 



Polyporus lucidus. The correct genus to which this plant belongs is 

 now known as Ganoderma, consisting of species with "varnished" pilei and 

 colored spores. Most of them, I think, are better called Fomes, but this 

 species with us is not perennial, hence not properly a Fomes. It is there- 

 fore a question whether to call it Polyporus lucidus, Fomes lucidus or Gano- 

 derma lucidus. It has been known, however, under the specific name 

 "lucidus" for more than a hundred years, and it is purely chimerical to try 

 to change that. 



Polyporus nidulans. Rather a rare plant in my experience. A curious 

 fact that is not generally known is a "chemical" test for it. Touch it with 

 a drop of ammonia, and the spot at once takes a bright violaceous color. 



Polyporus obtusus. Frequent and injurious on oak. A marked species 

 with large pores. The late Professor Ellis told me it could be found in 

 Schweinitz's herbarium under the name Polyporus unicolor, which I con- 

 firmed. Schweinitz badly described it, and gave it a worse name. When 

 one has a choice between two names for a plant, one very good, the other 

 very bad, and neither much used, I believe in adopting the better. Of more 

 interest than the name, however, is the structure of the plant, for it is a 

 Tnimetcx, not a Polyporus. 



Polyporus picipes. As I have always known it in the United States. 

 Claimed now to be different from the European plant, which, if true, is 

 unfortunate, as Polyporus picipes is an excellent name for it. 



Polyporus resinosus. Usually known under this name as found in Fries, 

 though I believe modern excavators have dug up older names for it. Very 

 common at Cincinnati. 



