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\_The Editor requests the assistance of Readers in answering Queries, so 

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Luminous Wood. — " Rotting wood is well known to be often phos- 

 phorescent ; and some authors state that this does not depend upon the 

 presence of fungi, but seeing the proved occurrence of phosphorescence in 

 the mycelium (spawn) of fungi, it is most probable that the luminosity is 

 attributable to them, especially as it is removed irrecoverably by drying up 

 the damp, rotten wood." — (" Henfrey's Elementary Course of Botany," ed. 

 Masters, 1870, p. 624.) The lumiuosity of fungi " has been observed in 

 various parts of the world ; and where the species has been fully developed 

 it has been generally a species of Agaricus which has yielded the pheno- 

 mena." Their luminosity at night " is often so intense as to yield light 

 enough to read by." " Tulasne, who has specially examined the luminosity 

 of the agaric of the olive {A. okarius), has observed dead leaves in the 

 south of France to be endowed with the same property, without, however, 

 being able to detect the cause. Fabre, in a paper just (1857) published in 

 Ann. D. Sc. Nat., ascribes it to a temporary increase of oxidation. Beautiful, 

 however, as the eflFect may be in these instances, it is far excelled by the 

 phosphorescent appearance presented by rhizomorphte in mines, the splen- 

 dour of which is described by Humboldt in the most glowing colours." 

 These are imperfect thalloid structures, which exhibit upon their branches 

 points of phosphorescence, sometimes so luminous " as to enable surround- 

 ing objects to be distinguished." "They are," the Rev. M. J. Berkeley 

 beUeves, " mere subterranean forms of common fungi. De Candolle long 

 since explained their real nature ; but it is very curious, if this be the case 

 that our common polypori and xylaria, which give rise notoriously to such 

 productions, are not themselves luminous when perfectly developed." 

 "According to Unger's observations, the light is not emitted from decay- 

 ing matter, but from a peculiar superficial layer of cellular tissue." — 

 (Henfrey, loc. cit., and Berkeley's " Cryptogamic Botany" (1857), p. 266.) 

 Microscopic observations and experiments on the life-history of these 

 fungi, and the natm'e of this phosphorescent light, would seem to be still 

 desirable. — G. S. Boulger, the Posting-house, Hemel Hempstead, Herts. 



As no scientific contributor has answered the question in relation to the 

 phosphoric gases produced by luminous wood, allow me to offer a few 



