390 



RESEARCHES ON FUNGI 



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FIG. 139. Psalliota campestris (wild form). Two cross-sections of gills. To show 

 exactly the angle of convergence of the opposite sides of each gill and the shape of 

 the interlamellar spaces as they are under field conditions. In cutting the sections 

 of the freshly-gathered living mushroom with a hand-razor, each gill became 

 unavoidably slightly curved to one side. The sections were mounted in water. 

 Camera-lucida drawings were then made which were subsequently very carefully 

 adjusted so as to make each gill look vertically downwards as shown above. 

 h, the hymenium. The trajectories or sporabolas of a few spores, as they are 

 in still air, are indicated by the arrows. The gills were originally 7 mm. deep. 

 The scale enables one to measure their thickness at various depths. 



