NORTH AM KMC AN ANTIIURUS. 



497 



the idea that the pseudoparenchyma develops from the hyphae both of the gleba and 

 of the gelatinous mass of the arm. The hyphae of this narrow layer are, however, in 

 direct connection with the hyphae of the cortical plate and through that with the cortical 

 layer, and stain the same. 



In Fig. 21, the small portion y of Fig. 20 is shown more highly magnified. On the 

 one side may be seen the gelatinous tissue of the arm, on the other there are the tramal 

 tissue and the hymenial surface with its constricted basidia here without spores. In the 

 space between may be seen the coarser and more irregularly shaped hyphae of cortical 

 nature, marked with irregular lateral inflations and taking on the form of intermediate 

 conditions of pseudoparenchyma. I am unable to find, in any of the many sections 

 examined, hyphae passing from the gelatinous tissue of the arm on the one side or from 

 the gleba on the other into the space between, and there forming pseudoparenchyma by 

 abjointing or constriction of their swollen tips. 



The wall of the stipe is now in an instructive stage of development. Serial radial 

 longitudinal sections are shown in Figs. 22 and 23. Two quite distinct tissues are present, 

 as was pointed out in the younger stage. One of these consists of hyphae running in 

 general in a longitudinal direction. These resemble the hyphae of the main cavity of 

 the stipe and those of the gelatinous tissue of the arms. At most places in the section, 

 of which only a small portion has been drawn, these hyphae are in small oblong or 

 linear masses separated from each other by a more deeply stained tissue. The oblong 

 masses lie in chambers which become empty at the time of elongation of the stipe. The 

 deeply stained walls of the chambers are not yet folded ; they consist of an early stage 

 of pseudoparenchyma. 



Although at some places in these sections and often in whole sections (Fig. 23), the 

 oblong masses of hyphae in the chambers seem to be completely cut off: from other 

 masses of similar nature by the chamber walls, yet the examination of the preceding or 

 following sections in the series will show small openings in the walls through which 

 hyphae pass from chamber to chamber. Such an opening is shown at z, Fig. 22. This 

 section was next in the series to that represented by Fig. 23. 



Sections of the middle and upper portions of the stipe do not show bundles of 

 hyphae passing from the medullary tissue of the main central cavity outward into the 

 chambers of the wall. But near the base fewer layers of chambers occur in the wall, 

 and bundles of hyphae do pass from the medullary tissue of the axis into the chambers 

 through small openings in their walls. Such entrance of the medullary tissue into the 

 chambers may be seen at the points b", Fig. 10, which represents a median longitudinal 

 section through the base of an egg in a still older stage of development. 



