LUMINESCENCE IN THE FUNGI 
William A. Murrill 
The phenomenon of phosphorescence, or luminescence, in liv- 
ing organisms has long been known and wondered at, but there 
remains much to be learned about the entire subject. The light- 
bearing fishes of the deep sea, the “ sparkling ” waves at the 
sides of a ship on a dark night, the firefly and glowworm, and 
luminous bacteria occurring on decaying fish, cabbage, etc., are 
well known. Molisch’s bacteria lamp designed for mines and 
powder magazines was an attempt to put this process of slow 
oxidation to some practical use. 
In animals, the light is usually brief and intermittent, while cer- 
tain fungi may give ot¥ light continuously for days, weeks, or even 
months, so long as the light-giving cells are uninjured and active 
and water is present. This light-giving power is recognized as 
useful to animals, but is probably without biological significance 
in plants. One can hardly believe that the spores of Clitocybe 
illudens, for example, are distributed to any great extent by the 
moths and fireflies that happen to be attracted by the weird light 
emanating from its spore-bearing surface. 
In some fungi, the power of luminescence is confined to the 
active cells of the mycelium. This is true in the case of Aymil- 
laria mellea, which inhabits old stumps and often causes them to 
glow on dark nights. While the rhizomorphs of this species are 
covered with active hyphae, they are luminous, but when they 
form a cuticle and enter the resting period the luminosity disap- 
pears. The mycelium of the hymenophore of this species is not 
luminous even when most active. 
On the other hand, the sclerotia of Collybia tuberosa are said 
to be luminous ; and the writer has observed that the mature 
hymenophores of Panns stypticus may be luminous when the 
young ones are not. Xylaria Hypoxylon is reported luminescent 
when growing naturally but not in pure cultures, which may pos- 
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