MISSOURI BOTANICAL GARDEN. 



in diseased wood of Libocedrus decurrens. At a one of 

 the attachment organs has formed a branch. These organs 

 adhere very firmly to the walls against which they are 

 pressed ; from the curved form of the hypha one is led to 

 suppose that the pressure exerted by the hypha must be 

 considerable. The reason for supposing these brown 

 hyphae to be saprophytic is that they are usually found 

 somewhere in the wood near a knot hole, where there is 

 abundant opportunity for the entrance of saprophytes. 



In many cases a form of mycelium with very thick walls 

 occurs. This has few clamp connections and forms thick 

 felts in the holes. This was found only in logs after they 

 had been cut, so there is some reason for considering it as 

 foreign to the disease. The great age of many of the cypress 

 trees, and the consequent presence of numerous places where 

 branches have been broken off, allows many fungi to get in 

 which live on the dead and decaying wood, but which seem to 

 have nothing to do with the peckiness. Their presence makes 

 the study a difficult one at times, especially as they seem to 

 grow rapidly and fructify readily . Thus a number of spore 

 forms were met with, but in no case could these be brought 

 into any connection with the colorless mycelium. One 

 form was found very often (PI. 5, fig. 5) also frequently 

 present in diseased wood of Libocedrus decurrens and Juni- 

 perus Virginiana. The spores are almost round, about 

 1 p. in diameter, brown, with a distinct wall and a central 

 shining body which is not affected by reagents. Many of 

 the spores have short knobs. The spores occur in such 

 numbers in the wood around the holes that it seems proba- 

 ble that they were formed in chains and may be considered 

 chlamydospores. A number of times chains of two or 

 three were found with fine remnants of hyphae attached. 

 These spores were placed in cultures of dung, cypress agar, 

 and gelatin, but have so far refused to germinate. It is 

 possible that they represent some form of entophytic 

 organism (Chytridiaceae 9 Phytomyxae?) studied by 

 28 



