104 MISSOURI BOTANICAL GARDEN. 



in the mycelium or the fruiting bodies. None of them are 

 considered as important in their effects upon the value of 

 the lumber, as the mycelium does not penetrate deeply into 

 the wood. Those identified were: Altemaria tenuis Nees, 

 Stachybotrys dlternans Bon., Ckaetomium sp., Aspergillus 

 niger, Stemonites sp., and Gliocladium sp. 



iii. wood-reddening fungi. 

 1. Penicillium. 



The fact that Penicillium might stain wood was brought 

 to our attention during the year 1903. Some cultures of 

 Ceralostomella exigua were contaminated with a lemon- 

 colored fungus, which, under certain conditions, stained the 

 wood an orange red color. Upon isolation it was found to 

 be a Penicillium, which was dimorphous, having a fertile 

 mycelium with gray-green colored fruiting clusters, and a 

 sterile mycelium which assumed either a lemon color or an 

 orange red color, varying with the reaction of the medium 

 upon which it was grown, the former color being present 

 on acid media, and the latter on alkaline. 



This led to the study of Penicillium from various 

 sources, and from different kinds of wood. Some were 

 found to stain pine sap wood, under certain conditions, an 

 orange red color, others a crimson red, and still others, a 

 color intermediate between the two. At least three species 

 of Penicillium were found which were proven to stain 

 wood. These were often intermingled, sometimes with 

 each other, and at some times with Fusarium. This com- 

 plicated the problem, and the difficulty was further in- 

 creased by the fact that it is hardly possible to name cor- 

 rectly the color-producing species of Penicillium without 

 a long scries of cultures. The investigations of Dierck * 



* Dierck, F. Essai de revision du genre Penicillium. Ann. de la Soc. 

 de Brux. 1901. 



