MISSOURI BOTANICAL GARDEN. 



found In a number of cases. How common this is cannot 

 be said, as the number of specimens examined was from 

 but a small number of trees. The threads have marked 

 attachment organs (PL 5, fig. 9 " d-f ") which have 

 been described under the cypress disease. 



In the rotted wood, and particularly around the same, the 

 cells are often filled with great masses of spores like those 

 seen in isolated cases in the cypress (PL 5, fig. 2). These 

 spores are present in such numbers, that they often com- 

 pletely fill the tracheids. Several spores were found with 

 yery fine hyphae attached (fig. 5) and many showed small 

 knobs at one end. It will be necessary to see a large num- 

 ber of trees to determine where these spores came from. 



LOCALIZATION. 



The localization of the diseased areas is quite as marked 

 in Libocedrus as it is in Taxodium. One may have a 

 block of wood 3X3X1 in. which looks perfectly sound, but 

 when split longitudinally it may contain a sharply defined 

 lenticular hole. It is suggested that probably similar 

 reasons to those given for the cypress hold here. The 

 investigation with respect to this point is to be regarded as 

 but begun. When it becomes possible to grow the fungus 

 found in the holes one may expect to reach more decisive 

 conclusions. 



SUMMARY. 



In the foregoing, two forms of decay have been de- 

 scribed, one destroying wood of Taxodium distichum, the 

 other of Libocedrus decurrens. In both cases the wood 

 is destroyed in localized areas, which are surrounded by 

 apparently sound wood. The cell-walls are changed into 

 compounds which diffuse through the walls and fill the cells 

 surrounding the decayed center ; and these have been called 

 humus compounds. In both, a fungus mycelium occurs 

 with strongly marked characteristics, which flourishes 

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