496 



COMPARATIVE MORPHOLOGY OF FUNGI 



in many places, very much as we have seen in Gautieria graveolens. As 

 the gleba develops, the tramal plates bend and anastomose, forming 

 cavities similar to those of Rhizopogo?i, which the gleba resembles in 

 general appearance (Fig. 315, 4). 



Phallogaster continues this tendency with more highly developed 

 tramal plates. P. saccatus, on rotten wood in North America, has been 

 more fully studied (Thaxter, 1893; Fitzpatrick, 1913). Here the tramal 

 plates are definitely differentiated into primary and secondary plates, 

 the primary lacking a hymenium (Fig. 317, J.). In longitudinal section, 

 they appear as branches and hence are called columella branches (st. 

 zw); laterally they anastomose, forming radial, polyhedral cavities, 

 opening outward, whose tips lie at a on the upper surface of the colu- 



Fig. 317. — Phallogaster saccatus. 

 B. Section of mature fructification. 

 after Thaxter.) 



A. Diagrammatic section of young fructification. 

 C. Habit, showing dehiscence. (Natural size; B, C 



mella. In tangential section the walls of the cavities form a mesh. The 

 tips of the primary branches spread out under the peridium to scutellate 

 plates, which are called volva gel plates Vg. Rudiments of these struc- 

 tures are also present in Hysterangium Fischeri of California where the 

 ends of the tramal plates broaden so much that inside the peridium 

 they form a narrow layer, only occasionally pierced by tortuous cavities 

 (Fischer, 1908). This layer is more or less gelatinous. 



The fertile secondary plates arise from the primary plates, as in 

 Maccagna; thus being retarded both in time and place of formation. 

 They push into the polyhedral cavities and converge between the plates 

 VG. In the limited space they lie in labyrinthine furrows and fuse with 

 the neighboring plates into a very tangled group of chambers. Although 

 the course of individual gleba chambers can no longer be followed, one 

 must still assume that they remain open outward toward the peridium. 

 The surface of the tramal plates is covered by a hymenium of 6- to 

 8-spored basidia. At the ends of the tramal plates in the gaps between 



