8o8 THE POPULAR SCIENCE MONTHLY. 



bia. The light, however, is usually emitted by the organs of- reproduc- 

 tion ; this is particularly the case in young fungi, while, in the older 

 ones, after the luminosity has disappeared from the gills, the surface 

 of the stipe becomes radiant. 



The mycelium of the root-shaped fungi (rhizomorpha) penetrates 

 through the decaying organic matter of wood and coal deposits, ex- 

 hibiting a clear pale light. This has been particularly observed in the 

 mines near Dresden, Hesse, and occasionally in England. These flower- 

 less, gleaming plants impart a weird beauty to the caverns of granitic 

 rock in Bohemia, illuminating them with a pale mimicry of moon- 

 light. 



The most remarkable instances of cryptogamic phosphorescence 

 have been noted by Mr, Gardner in Brazil, by Dr. Cuthbert-Colling- 

 wood in Borneo, by Mr. Hugh Low and James Drummond in Austra- 

 lia, and by Mr. Worthington-Smith in the Cardiff coal-mines. Rev. J. 

 M, Berkeley cites an instance in England, where a dazzling radiance 

 was observed upon a spruce or larch log, which continued for several 

 days — a byssoid mycelium, yielding an unusually pungent odor, being 

 recognized. The common potato also, in decomposing, generates a 

 peculiarly luminous parasite ; and, at one time, an alarm of fire was 

 sounded in the streets of Strasburg from the light produced by a de- 

 caying mass stored in a cellar. An instance has recently come to my 

 notice, where a brilliant light was thrown off by pieces of cantaloupe, 

 after a few hours' exposure to the air. 



Wherevei', then, we encounter decomposing vegetable matter, we 

 observe some form of fungi living upon and appropriating the changed 

 substances of a former condition to the generation of a new life. What, 

 therefore, seems to us a loss or waste, is merely change — change of form, 

 change of condition. The absorbing roots of these parasites grow into 

 the tissues of the host in the most intimate manner, deriving from a 

 disorganization of the substances the elements necessary to their own 

 being. 



Vergil describes the blighting mildew on the grain as " an unbidden 

 crew of graceless guests that choke the fields " ; and De Barry writes 

 that there is a frequent unbidden guest in every household, who lays 

 under contribution its stores of sweets. The mold or mildew which 

 gathers on the surface of preserves is a plant of exquisite beauty when 

 viewed with low magnifying power and by reflected light, for what 

 appears to the naked eye only a soft, white, woolly crust, becomes a 

 glittering forest of graceful stems and branches, standing like fine- 

 spun silver upon the dark background of the supporting surface. This 

 substratum is in reality a mycelium, or system of fine interlacing, 

 thread-like roots, which form the vegetative part of the plant, and are 

 woven into a soft, black or brown velvety substance, through which 

 run russet, scaly hairs. The branches rise to about the fiftieth of an 

 inch, and bear the fruit and seed-cells. Higher microscopic power 



