19 



and give oflf lateral branches. No mycelium is found in the sapwood. 

 The wood between the pockets has many hypha?, which pass from one 

 pocket to another. 



The brown humous compound found in Taxodium^ is entirely absent 

 in the tracheids of this intermediate wood. In Taxodium this sub- 

 stance was supposed to be active in restricting the growth of the myce- 

 lium to certain areas, 

 protecting, as it were, 

 the wood in which it was 

 contained. As a result 

 holes were formed which 

 rarely joined. In the 

 cedar the holes join as 

 a rule, forming very 

 large, irregular cavities, 

 and this would seem to 

 bear out what has been 

 claimed for Taxodium. 

 There being no restrain- 

 ing factor, the enzym 

 of the fungus acted in the 

 surrounding wood, mak- 

 ing the cavities larger 

 and larger. There is 

 practically no limit to 

 the carbonization of the 

 wood (PI. VI), for very 

 old trees may be almost 

 hollow at the base, and 

 it is no uncommon thing 

 for such trees to be 

 blown over when the 

 hollow becomes so great 

 that the sap wood is not 

 strong enough to keep 

 them standing. 



THE FRUITING BODY. 



. . Fig. 3.— Trunk of a red cedar showing hole under an old 



The fruiting body of branch. 



the fungus, which was 



long sought for, forms in the holes so common on the trunk of the 

 cedar and which are brought about by the manner in which the dead 

 branches seem to recede into the trunk (fig. 3). The cedar belongs to 

 that class of trees in which the base of a dead branch does not grow 



^ von Schreuk, 1. c, p. 14. 



