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1917] FITZPATRICK—RHIZINA UNDULATA 289 



and interlacing in every direction along the surface form a matted 

 web 2-8 threads in thickness. This membrane is very transitory, 

 however, and undergoes degeneration at an early period. .Its 

 protoplasm takes on a granular appearance, the cell outlines 

 become indistinct, and finally the whole disintegrates into a 

 deeply staining mass in which the nuclei are the most prominent 

 feature. Long before the process is complete, however, the rapid 

 growth of the underlying tissue bursts the envelope so that it 

 adheres in flakes (figs. 57, 58). Then the paraphyses and inter- 

 calary palisade hyphae pushing out to the surface complete the 

 separation and all traces of it are cast off." 



McCu 



m 



crographs of stages younger than that shown in his fig. 57. If 

 in Helvetia, as he states, the envelope, which incloses the fruit 

 body in the early stages, arises from the palisade layer, it might be 

 concluded that the section of Rhizina undulata shown in fig. 2 is 

 too young to possess the envelope, and that it might logically be 

 expected to develop later on older fruit bodies. That it does not 

 do so, however, is certain. The writer has had available a suf- 



number 



mi 



to this point. 



No veil or fragm 

 bodies sectioned. 



Figs. 3-6 show median longitudinal sections through primordia 



ma 



somewhat older than that pictured in fig. 2. The 



the 5 cases is the same, being 40 diameters. Other fruit bodies 



sectioned, of intermediate sizes, bring out no additional facts. 



In fig. 3 



hyphal arrangement at the 



m 9 



periphery is evident. The deep-staining area on the upper surface 



gm 



/ in trimming the print. Other 

 sections of similar rootlets appear at different places in the interior 

 of the fruit body. At the base of the ascocarp can be noted the 



tendency of the mycelium 



These young 



rhizoids appear in section in figs. 3, 5, and 6. Fig. 5 shows the 

 palisade layer of hyphae very clearly. In fig. 10 a portion of the 



same 



