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RESEARCHES ON FUNGI 



from the gun at the moment when the inner membranes of the cup 

 attain their maximum degree of e version. 



The outer envelope of the glebal mass is dark reddish, changing 

 to black with age. The pigment, which resides in the cell-walls, 



Fig. 147. — Sphaeroboius stellatus. Diagrammatic median vertical 

 sections through the mature fruit-body. A, shortly before 

 opening stellately ; B, after opening stellately and just before 

 the discharge of the gleba ; C, just after the discharge and dis- 

 appearance of the gleba. The four layers of the peridium, from 

 without inwards, are : m, the gelatinous layer ; p, the pseudo- 

 parenchymatous layer ; /, the fibrous layer ; and c, the recep- 

 taculum or palisade layer. The gleba, sp, is shot away from the 

 fruit-body by the sudden eversion of the peridial layers / and c. 

 After E. Fischer. About 20 times the natural size. 



may be merely a useless product of metabolic activity. On the 

 other hand, there is the possibility that it serves as a light-screen 

 and protects the colourless spores and gemmae lying in the gleba 

 from injury by sunlight whilst the glebal mass is attached to herbage. 

 Such a function may also be ascribed to the dark pigment in the 

 black sporangial wall of Pilobolus and in the dark inner walls of the 

 spores of Ascobolus immersus — two other fungi in which the pro- 



