FUNGI. 213 



of the pilcus, or its cuticle, which I have never seen 

 luminous. 



"As I have said, the agaric of the olive tree, which 

 is itself very yellow, reflects a strong brilliant light, 

 and remains endowed with this remarkable faculty 

 whilst it grows, or, at least, while it appears to pre- 

 serve an active life and remains fresh. The phospho- 

 rescence is at first, and more ordinarily, recognizable 

 at the surface of the hymenium. I have seen a great 

 number of young fungi which were very phospho- 

 rescent in the gills, but not in any other part. In 

 another case, and amongst more aged fungi, the 

 hymenium of which had ceased to give light, the 

 stipe, on the contrary, threw out a brilliant glare. 

 Habitually the phosphorescence is distributed in an 

 unequal manner on the stipe, and the same upon the 

 gills. Although the stipe is luminous at its surface, 

 it is not always necessarily so in its interior substance, 

 if one bruises it ; but this substance frequently be- 

 comes phosphorescent after contact with the air. 

 Thus I had irregularly split and slit a large stipe in 

 its length, and I found the whole flesh obscure, whilst 

 on the exterior were some luminous places. I roughly 

 joined the lacerated parts, and the following evening, 

 on observing them anew, I found them all flashing 

 a bright light. At another time I had with a scalpel 

 split vertically many fungi in order to hasten their 

 dessication ; the evening of the same day the surface 

 of all those cuts was phosphorescent, but in many of 

 these pieces of fungi the luminosity was limited to 

 the cut surface which remained exposed to the air, 

 the flesh beneath was unchanged. 



