GASTEROMYCETES 499 



columns. Our Figs. 319, 320 may be distinguished from the corre- 

 sponding stage in Protubera (Fig. 318) by the smaller number of branches 

 of the central columella and by a greater development of the separating 

 portions of intermediate tissue: further, the separation into columella 

 and tangled intermediate tissue spreads over the whole fructification. 

 In the Protubera stage (Fig. 318, 2), the articulation of the columella is 

 still incomplete, as the tissue indicated as such includes the whole central 

 and basal mass of the fructification. In Clathrus, however, the separation 

 continues to the base, and the columella becomes a true central axis 

 surrounded by peripheral tissue. 



As in Protubera, the hyphal palisade HA, which later expands later- 

 ally, is laid down in the corners between the branches of the columella 

 (Fig. 319, 2), and the intermediate tissue is compressed by the developing 

 columella branches, especially at the periphery where these branches 

 spread out into gel plates VG. In the central parts, however, there 

 remains more space for the intermediate tissue. In contrast to Protubera 

 (herein lies the distinct progress over this genus), these parts of the 

 intermediate tissue are not dissolved and there are differentiated from 

 them, at least in Clathrus cancellatus (toward the hyphal palisade HA), 

 a thicker hyphal knot Rp (the first fundament of the receptacle, which 

 is separated from its surroundings by a loose layer of tissue. In time 

 the peripheral hyphae become arranged in a palisade. 



The strong sidewise growth of branches of the columella is very 

 marked (Fig. 319, 3); in section, the parts VG represent polygonal areas 

 which are continued by the narrow plates of intermediate tissue and 

 separated from one another, but are beginning to gelify. 



Further, especially in the upper portions of HA , the columella branches 

 elongate radially, whereby the hyphal knot Rp is pushed away from 

 the palisade HA, and shoved outward so that a cavity arises between 

 Rp and HA. This cavity is surrounded by a hyphal palisade, the lateral 

 continuation of the original palisade, and is the first glebal chamber Gl. 

 Km. In the distal side of the first hyphal knot Rp, in C. cancellatus, 

 further knots are separated from each other and their surroundings by a 

 narrow layer of loose tissue, the separation being most complete in the 

 older inner knots, less complete in the outer. 



By the radial elongation of the columella branches, the gleba chambers 

 increase in size (Fig. 319, 4). Meanwhile individual portions of the wall 

 of the branch of the columella, covered by the hymenial palisade, arch 

 over in ridges, elongate, increase in number, branch and eventually form 

 the labyrinth of cavities and tramal plates which characterizes the gleba 

 of the Gasteromycetes. In the distal parts of the gleba, where this touches 

 the intermediate tissue, the hyphae of this tissue grow into the glebal 

 chambers, fill them, hinder the change of the palisade to hymenium and 

 intertwine repeatedly to a pseudoparenchyma. Similarly, the palisades 



