272 RESEARCHES ON FUNGI 



C shows the appearance of the three gills when looked at edgewise from the stipe. 

 The arrows indicate the sporabolas or paths taken by the spores when escaping 

 from the gills. 



Figs. 18-20 all of Coprinus micaceus. 



FIG. 18. Young fruit-body from which spore-liberation has begun. Natural 

 size. 



FIG. 19. Vertical section through a young fruit-body before spore-liberation 

 has begun. The gills are turning brown and ripening their spores from below 

 upwards. Natural size. 



FIG. 20. a, ft, c, and d. Successive stages during the autodigestion of the 

 gills. Drawn from four different fruit-bodies. Natural size. 



PLATE IV 



Figs. 21-24 all of Coprinus comatus. 



FIG. 21. Characteristic group of fruit-bodies growing in a field. Owing to 

 excessive crowding, parts of the free margin of the pileus of two individuals have 

 stuck to younger fruit-bodies. Magnification about 6. 



FIG. 22. Specimens placed in a row and photographed to show the various 

 stages of development. The gradual opening out of the pileus and the curling up 

 of its free margin during autodigestion, and also the lengthening of the stipe, 

 may be traced from right to left. Magnification about 7. 



FIG. 23. Underside of a fruit-body liberating spores. Autodigestion is 

 taking place where the gills look black and are evidently separated by free 

 spaces. Spores are being discharged into the air from hymenial zones just above 

 and parallel to the wet gill edges. The inner and higher parts of the gills, where 

 autodigestion is not yet taking place, are still united at their edges by the large 

 white cystidia. Natural size. 



FIG. 24. Photograph of a helmet-shaped fruit-body in a field. A marked 

 feature is the outwardly folded remains of the gills at the free margin of the 

 pileus. A drop of " ink " hangs from the pileus opposite the stipe. The dark 

 liquid drop is in such a position that it does not interfere with the discharge of 

 the spores into the air. Magnification about ^. 



FIG. 25. View of the underside of a mature pileus of Psalliota campestris 

 grown on a Mushroom bed. The gills are horizontally outstretched and free 

 from each other throughout their length. Spores are liberated from all the inter- 

 lamellar spaces and from every part of them simultaneously. Natural size. 



FIG. 26. The Poynting Plate Micrometer and a microscope for using it. The 

 glass plate, p, can be pushed into the slot si. The stand, st, has a vertical arm, a, 

 with a scale, sc. The plate, p, is attached to the horizontal rod, r, which can be 

 rotated by means of the lever, I, which terminates in a small framework carrying 

 a piece of glass on which is etched a line parallel to the lever. For further 

 description see the text. 



FIG. 27. Polyporus squamosus. Spore-deposit made in about twenty-four 

 hours from the hymenial tubes of a piece of the pileus. Each tube has produced 

 its own heap of spores. Natural size. 



FIG. 28. Polyporus squamosus. Spore-deposit made in about twenty-four 



