CRYPTOGAMIC PLANTS. 91 
But nowhere, perhaps, is the effect produced by 
this cryptogamic phosphorescence so exquisitely 
beautiful as in the mines of Hesse, in the north of 
Germany, where the walls of the air galleries ap- 
pear illuminated with a pale heht resembling that 
of the moonbeams stealing through narrow cre- 
vices into some gloomy recess. 
Some other species of Rhizomorpha are sup- 
posed to be luminous, but this is doubtful. Heinz- 
mann says he has remarked phosphorescence in 
Lt. subterranea and in Rh. aidule. 
Certain experimentalists think that the hight of 
these fungi is more brilliant in oxygen gas than 
in the air, and that it is extinguished in those 
gases which are non-respirable ; whilst others, on 
the contrary, have asserted that though hydrogen 
gas, hydrochloric acid, and nitric oxide, seem to 
put out the heht of many phosphorescent fungi, 
this hght is not extinguished in pure nitrogen. 
These observations require, therefore, to be re- 
peated with care. 
Phosphorescence appears to have been first ob- 
served in large fungi at Amboine, by the botanist 
Rumphius, who saw light emitted from a species 
he has designated Fungus igneus, or fire-mush- 
room. It was afterwards seen in the Brazils by 
another botanist, Gardner, upon an agaric, which 
grows on the dead leaves of the Pindoba palm, 
and which has been named Agaricus Gardneri. 
