THE GENUS HEXAGONA. 



Definition. The genus Hexagona can be described in a few words 

 as being fungi with large, round or hexagonal pores, or Polyporus 

 with large, round or hexagonal pores. It is a tropical or sub-tropical 

 genus, and does not occur in temperate regions. Theoretically the 

 genus is purely artificial, based on a single character, but it is a very 

 convenient genus, and to attempt to break it up would only make a 

 needless complication. 1 



In context Hexagonas are usually corky-woody, and as Fries knew 

 only such species, he specified this as a character of the genus. There 

 are a few species with hexagonal pores of which the context is rather 

 fleshy-cartilaginous. We should include them also in Hexagona, be- 

 lieving it to be better to take the genus literally on its pore character. 



Size of the pores. While the basic idea of the genus is large, 

 round or hexagonal pores, the word large is, of course, only relative. 

 There has been associated (unintentionally perhaps) with the genus 

 Hexagona the idea of regularity of pores. Thus there is a series of 

 forms related to Hexagona tenuis which have by common consent 

 always been classed in Hexagona. The pores are rather small, but 

 they are regular and shallow. Many other polyporoids with larger 

 pores are classed with Polyporus or Trametes when the pores are 

 deep. 



There is also a group of species, such as Polystictus pinsitus, with 

 equally as large and as shallow pores, but they are irregular, with 

 thin, angular, uneven pore-walls. This section is generally included 

 in Polystictns, and I think that is preferable, but sometimes species 

 of this section have been called Hexagona. 



Spores. The color of the spores was not taken into account by 

 the old authors in the genus Hexagona, but as they are practically 

 all supposed to have white spores, we should make that a character 

 also of the genus. We have never seen a single spore of any species 

 of what we include in Hexagona, as spores of white-spored poly- 

 poroids are rarely found in herbarium specimens. But the fact that 

 we do not find the spores is a strong evidence that they are white. 2 



J Any one who is so disposed, however, can discover as many and as useless "new genera" 

 in it as have several times been discovered in Polyporus. 



= It is well known that species of polyporoids with colored spores have the spores, usually 

 (if not always) in abundance. I have no doubt that all Hexagonas have white spores, though 

 I have not positive evidence of the fact in a single instance. 



