COPRINUS STERQUILINUS 



191 



When the pileus is barrel-shaped, just before its expansion 

 begins, the gills are all compactly crowded into a relatively small 

 space ; but, as the pileus expands, the interlamellar spaces increase 



Fig. 79. — Coprinus sterquilinus. Parts of three gills of Fig. 78 showing 

 in detail the structure of the swollen gill-edges or flanges and how 

 by the presence of these flanges opposing hymenial surfaces are 

 kept from rubbing against one another. Into the interlamellar 

 space, t, the dimorphic basidia are projecting ; /, a flange formed 

 by the incurved edges of a gill ; a, a large air-space ; j, place of 

 junction of two flanges. Cystidia are absent from the gill-sides ; 

 the swollen cells on the exterior of the flange, /, are large and 

 sterile. Magnification, 86. 



in width, so that finally each gill is freed from its two neighbour.:; 

 and provided laterally with two large interlamellar spaces into 

 which it may discharge its spores without any risk of their striking 

 obstacles. The width of these interlamellar spaces in a fruit-body 

 tvhich has become helmet-shaped is shown in Fig. 101, A (p. 237). 

 In the piece of pileus shown at B in Fig. 80, the number of the gills 



