GASTEROMYCETES 



501 



which in C. cancellatus surround the knot Rp, change into pseudoparenchy- 

 matous tissue. This collective pseudoparenchyma later gives rise to the 

 receptacle walls. In C. columnatus, they arise singly from the hyphae 

 of the intermediate tissue which eventually grow luxuriantly between the 

 peripheral tramal plates; in C. cancellatus independent hyphal knots, 

 which already have been differentiated in the intermediate tissue, partic- 

 ipate in the formation of the receptacle walls. On account of the close 

 contact which is formed by the growth of the hyphae of the intermediate 

 tissue into the peripheral glebal parts, the gleba remains suspended 

 after elongation of the receptacle. 





-. 

 '.■■■*',: 



<tft. p* 



Per. V. G, Zw.cj4ff.pC Rj>.' Km Rp\vd 



Fig. 320. — Clathrus columnatus. 1. Vertical section of fundaments of a fructification. 

 2. Horizontal section. 3. Same, older stage. 4. Older stage, showing fundaments of 

 first glebal cavities and tramal plates. 5. Older stage. Intermediate tissue has grown 

 into the peripheral chambers forming pseudoparenchyma, Rp. wd. 6. Longitudinal sec- 

 tion of mature egg at beginning of elongation of receptacle. Letters as in 317, except 

 Rp. Km. receptacle chambers; Rp. wd., wall of receptacle chambers. (1 to 4 X 30; 5 X 

 17; 6 X 3; after Burt, 1896.) 



Toward the end of the development, the hymenial palisade changes 

 to hymenia of eight-spored basidia. The parts of the intermediate 

 tissue and gleba surrounded by the receptacle walls gelify, so that recep- 

 tacle cavities result. 



Figure 319, 7 is a medial cross-section through a so-called egg, i.e., 

 an immature fructification shortly before expansion. The axis of the 

 greenish gleba Gl, occupying the greater part of the space, is penetrated 

 by the columella which soon swells. The rays which proceed from it are 

 the branches of the columella. On account of their tortuous course 

 they cannot be followed to the volva in a section; furthermore, in contrast 

 to Hysterangium, they are very thin in comparison to the gleba and 



