THE SPHAEROBOLUS GUN 309 



A glebal mass, at the time of its discharge, is illustrated in Fig 146 

 (p. 295) and has already been described. Its gleba differs from the 

 gleba shown in Fig. 154 in that the glebal chamber- walls have 

 disappeared (cf. Figs. 146 and 154), the fat cells have broken down, 

 and the spores, gemmae, and cystidia have all become embedded 

 in a fatty matrix. 



Fourteen of the large rounded cells known as cystidia which are 

 present in a glebal mass at the time of its discharge (cf. Fig. 146, 

 p. 295) are shown in Fig. 155. These cells form a layer at the 

 periphery of the gleba (Figs. 146 and 154) and are scattered sparsely 

 throughout the glebal mass among the spores. 



Gemmae, peculiar oval or oval-elongated cells which are present 

 in the gleba scattered among the spores before and after the 

 glebal mass has been discharged, are illustrated in Fig. 156. On 



Fig. 154.- — Sphaerobolus stellatus. A, a vertical section, and B, tangential sections, 

 of an unopened fruit-body, including all the layers of the peridium and part 

 of the gleba, to show details of structure. The fruit-body was approaching 

 maturity and would have discharged its glebal mass on the next day. A, a 

 vertical section of the lower part of the fruit-body showing the peridium with 

 its six layers, nos. 1-6, and the gleba g. The peridial layers are : no. 1, a 

 mycelial layer, the hyphae with thin walls and having clamp-connexions c c at 

 the septa ; no. 2, a gelatinous layer, consisting of well-separated thin-walled 

 hyphae h bearing clamp -connexions, the hyphae embedded in a gelatinous 

 matrix j formed by the swelling of the outer hyphal walls ; no. 3, a fairly thick 

 pseudoparenchymatous layer with wide hyphal cells t in the transition zone below 

 and pseudoparenchymatous cells p above, with air-spaces s between the elements; 

 no. 4, a fibrous layer made up of interwoven, mostly tangential, thick-walled 

 hyphae / with air-spaces i between them ; no. 5, the palisade layer, made up 

 for the most part of radially elongated, relatively thick-walled, mutually 

 adherent cells m, with shorter cells I below and the uppermost cells u rounded 

 and with walls specially thickened (the glebal mass eventually separates from 

 the palisade layer just above the cells u) ; no. 6, a thin pseudoparenchymatous 

 layer made up of small pseudoparenchymatous cells p with intercellular spaces s 

 between them. The gleba g contains peripherally a layer of rounded cells a a 

 known as cystidia and within is made up of small chambers, several of which 

 are in view. The partition walls of the chambers are made up of ordinary 

 thin-walled hyphae b b, which may bear clamp-connexions, and of much-swollen 

 fat cells c c whose glutinous contents have not yet been liberated but will 

 eventually be set free and come to form a matrix in which the spores, gemmae, 

 and cystidia will be embedded. Loosely scattered in the chambers, from which 

 the basidium- bodies have now disappeared, are : very numerous oval thick- 

 walled spores d d ; less numerous, thin-walled, more or less oval-elongated 

 gemmae e e ; and a few spherical cystidia like those already mentioned at a a. 

 B, a series of eight tangential sections through the peridium and gleba ; 

 letters with the same explanations as for A : nos. 1-6 represent tangential 

 sections taken through the central parts of layers nos. 1-6 in A. The two 

 drawings o and i represent tangential sections taken through the gleba, the 

 former through the outer layer made up of cystidia, ordinary hyphae, and 

 gemmae, and the latter through the inner region made up of glebal chambers. 

 Drawn by A. H. R. Buller and Ruth Macrae. Magnification, 350. 



