EXPLANATION OF PLATES l.-V 



PLATE I 



FIG. 1 Coprinus comatus. Vertical section through a large fruit-body showing 

 the thin flesh, the vertically-placed gills, darkening from below upwards, and the 

 hollow stipe, m, marginal band covered with cystidia. Natural size. 



FIG. 2. Psalliota campestris. Section through a ripe fruit-body at maturity to 

 be contrasted with that of Coprinus comatus in Fig. 1. Its flesh is thick, and the 

 gills are nearly horizontally outstretched. Specimen obtained from a field. 

 Natural size. 



FJG. 3. Section through the hymenium of Polyporus squamosus, constructed 

 from sketches made with a camera lucida. , a basidium with unripe spores ; b, 

 a basidium with ripe spores ; c, a basidium with two of its spores already dis- 

 charged ; d, a basidium which has discharged all four spores. Paraphyses separate 

 the basidia. Magnification, 625. 



FIG. 4. Psalliota campestris. Vertical and transverse section through three 

 gills. The hymenial surfaces are almost vertical. The arrows indicate the spora- 

 bolas or paths described by spores after violent discharge from the sterigmata. 

 Each spore is shot outwards horizontally to a distance of (H-0'2 mm., and after 

 making a sharp turn falls vertically downwards in the space between the gills. 

 Magnification, 25. 



FIG. 5. Coprinus comatus. Transverse section through some of the gills 

 whilst the spores are ripening, s, s, spaces between the gills lined by the 

 hymenium ; e, inner swollen edges of gills covered with cystidia ; /, pileus flesh. 

 Magnification, 8. 



PLATE II 



Figs, all of Coprinus comatus. 



FlG. 6. Vertical section through a young fruit-body shortly after it had 

 appeared above the ground, s, level of soil. Natural size. 



FIG. 7. Vertical section through an older fruit-body shortly before the gills 

 separate from the stipe, s, level of soil. Natural size. 



FIG. 8. Vertical section through a fruit-body after autodigestion has begun. 

 The gills are becoming liquefied from below upwards. The dotted lines show the 

 shape and position of the gills at the moment autodigestion began, s, lower 

 edge of gill where spore-discharge and subsequently autodigestion first become 

 active ; , oblique edge of gill where spore-discharge and autodigestion are taking 

 place ; m, marginal band on gill edge covered with cystidia. Natural size. 



FIG. 9. Vertical section through a fruit-body which has become helmet- 

 shaped. By autodigestion the gills have now become reduced to about one-third 

 their original length. , edge of gill where spore-liberation and autodigestion 



270 



