98 MISSOURI BOTANICAL GARDEN. 



2. HORMODENDRON. 



An intense black color in irregular blotches often oc- 

 curs on new pine, elm, ash, gum, oak, and other kinds of 

 lumber, when sawn under a moist condition, during warm 

 weather. A large number of such spots were examined, 

 and the fungi present isolated for investigation. Species 

 of Hormodendron, Hormiscium and Altemaria were found 

 present. Two species of Hormodendron were identified, 

 viz: H, cladosporioides (Fres.) Sacc. and a species not 

 agreeing with any description previously published, and 

 which is here given the name H. griseum. 



Inoculations of these two species were made upon pine, 

 elm, oak, ash and guwn wood. Both species were found to 

 produce superficial black stains, but neither penetrates 

 deeply into hard woods. On the other hand, either species 

 penetrates deeply boards made from the red gum tree, 

 Liquidambar Styraciflua L. Under the microscope the 

 conidial clusters of the two species closely resemble each 

 other, but in cultures the gross appearance of the colonies 

 is constantly quite different, the former varying from a 

 yellow-green to a dark olive, or almost black, the latter 

 from a light gray to a color approaching black; other 

 differences were noted in the length of the couidiophores 

 and of the conidial chains. 



Hormodendron cladosporioides (Fres.) Sacc. 



The species of Hormodendron most commonly found on 

 boards is described here from artificial cultures, and 

 assumed to be H. cladosporioides. Two other species oc- 

 curring on wood, which have been previously described, 

 but at a later date, are //. atrum Bon. and //. elatum 

 Hartz. From the description of these two latter species 

 it would be very difficult to separate the one from the 



