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FIG. 89. Panaeolus campanulatus. Part of the hymenium on the side of a gill, 

 showing the spores only, sketched with the help of a camera lucida on the second day 

 of spore-discharge. The dotted lines have been added in order to enable the eye to 

 distinguish more readily the darker and lighter areas of the mottled hymenium. In 

 the darker areas the spores are black, and either ripe or nearly ripe. In the lighter 

 areas the spores are either colourless (unshaded) or are beginning to turn brown 

 (shaded with dots). All the spores in the central dark area are of approximately equal 

 age and will be shot away approximately at the same time. Another generation of 

 basidia will then produce colourless spores in this area which will then be white ; then, 

 as the spores become pigmented, the area will gradually change from white through 

 brown to black again. The white areas shown in the illustration are destined to turn 

 black owing to the ripening of the spores ; after the spores have been shot away, they 

 will become white again, y, spores not 15 minutes old, rapidly developing in size ; 

 2, ripe spores shortly before discharge, about 9 hours old. At a, 6, and c, the 

 basidia have just discharged some of their spores. The heaps of spores at d were 

 produced owing to excessive excretion of water from the sterigmata, which took place 

 whilst the sketch was being made under very moist conditions. Had the conditions 

 been normal, the basidia concerned would have discharged their spores into the air. 

 The blank spaces at e and at the other corners of the drawing are due to the fact 

 that the spores present in these areas were not sketched. In the blank space at /, 

 several basidia have just discharged their spores : in this area the basidia of the next 

 generation are completing the development of their sterigmata just prior to the pro- 

 duction of spores. The area sketched = 0'25 square mm. Magnification, 220. 



