CHROMOGENIC FUNGI WHICH DISCOLOR WOOD. 101 



which was looked for. The following description of 

 H. griseum is made from cultures grown on the same 

 media from which the characters of H. cladosporioides 

 previously given were obtained : — 



Mycelium. 



The conidia of this species germinate readily, and simi- 

 larly to those of the preceding species, but the colony is a 

 day or two longer in producing conidia than that of the 

 former species. The habit of fruiting is the same, but the 

 conidia are borne in longer chains. The mycelium is 

 coarsely granular, and thick-walled in the older filaments, 

 which measure from 3/t to 10/u, in diameter. The sporo- 

 phores or fruiting hyphae measure 200/*. to 800/t in length, 

 and 3/u- to 4/j. in diameter. The hyphal branches are in 

 two series, and are from 1- to 3- septate, measuring 6^ 

 to 14/i by 3/x to 4/-*. 



Conidia. 



The conidia are borne in branching chains of 2 to 10, 

 and are formed from the ends of the hyphae by abstriction 

 (pi. 10, f. 2). They are of a sooty color, pointed oval, 

 and measure 3/z to 6/x by 2/j, to 4/z. 



3. Hormiscium. 



Hormiscium gelalinosum n. sp. 



In the study of the black stain of pine, elm and red gum 

 boards at least one species of Hormiscium was found caus- 

 ing a very intense black stain, especially in sapwood. It 

 is with some hesitancy that this fungus is named Hormis- 

 cium in view of the great resemblance of the mycelium on 

 agar plate cultures to some of the forms of Dematium pul- 

 lulans de Bary, found by Planchon* in his study of the 



* Planchon, Louis. I. c. 



