264 LUMINOUS FUNGI. PART n. 



probably from ozone. In all fungi there is a small 

 amount of poisonous matter, and the quantity in any 

 given species is extremely uncertain, so that the same 

 fungus which may be eaten with safety in one country, 

 is deleterious in another. 



In the dark coal mines at Dresden, luminous Fungi 

 cover the roof and pillars with the most dazzling phos- 

 phorescent light, which increases with the temperature 

 of the mine. Agaricus Gardneri, a species parasitic on 

 the Pintado palm in Brazil, is highly luminous ; and 

 the Agaricus olearius in the south of France also pos- 

 sesses that rare quality. The gills under the pileus shine 

 as brightly as a glow-worm, in the dark crevices of the 

 olive stems in November and December. M. Tulasne 

 found that the light was extinguished in vacuo or non- 

 respirable gases, whence he concludes that it is due to 

 a slow combustion without heat, arising from a chemical 

 combination of the oxygen of the atmosphere, inhaled 

 by the fungus, with a substance peculiar to the plant. 



In a few Agarics the cells are so connected by veins 

 or lateral branches, that they assume the character of 

 pores, as in the Chantarelle, a sweet-scented lemon- 

 coloured fungus, whose gills pass into mere veins, and 

 its inferior fruit-bearing surface is all but even and 

 uniform, so that it forms a connection between the 

 Agarics and the Polyporei, a most extensive order of the 

 higher fungi, essentially distinguished by having a mul- 

 titude of pores in the smooth under-surface of the pileus, 

 instead of gills. The pores are generally small ; in some 

 species they are hexagonal, and so large that they look 

 like a honeycomb. In all, they are the mouths of cel- 

 lular tubes, packed closely together side by side, or more 

 closely connected, sometimes easily separated, sometimes 

 inseparable. They constitute the fructiferous surface 

 or hymenium of the fungus, and contain the spores. 

 This structure gives the pileus a thick heavy appear- 



