inOLUMINESCENCE OF DECAYINCi LEAVES 423 



of the Iccavcs were luminous over nearly their whole surface or in 

 patches. I soon picked out thirty Beech leaves and one Oak leaf 

 all of which gave out a soft whitish light. The light emitted was 

 not very bright, but it enabled me to distinguish the luminous 

 from the non-luminous leaves with ease and certainty. Thus, at 

 my vt^ry first attempt, I succeeded in obtaining luminous leaves 

 from forest mould. 



On June 17, I filled my attache case with decaying leaves taken 

 from the mould lying beneath certain trees in Kew Gardens. On 

 examining this booty at night in the dark, I found that many of 

 the Oak and Beech leaves were beautifully luminous. 



On August 4, I gathered a few handfuls of decaying Oak leaves 

 from beneath some trees in a wood at Tanworth-in-Arden, War- 

 wickshire. A number of the leaves, when examined in the evening 

 in the dark, were found to give out a soft' white light. The light 

 came from the whiter more highly decayed parts of the laminae 

 and not from the less decayed browner parts. 



In the third week of September, whilst attending the Keswick 

 meeting of the British Mycological Society, I made three small 

 collections of Oak leaves from as many different Cumberland 

 woods. Some of the leaves in each collection, especially those 

 exhibiting discoloured whitish or yellowish decay-spots, gave out 

 light. At a dark seance held at the close of one of the Society's 

 evening meetings, I demonstrated luminosity of the leaves to the 

 members in attendance. 



In July, 1923, in a wood at Four Oaks, Warwickshire, I col- 

 lected a large number of luminous leaves from the leaf -mould. 

 Most of them were Beech and Oak leaves but of the remainder 

 some undoubtedly belonged to the Spanish Chestnut [Castanea 

 vesca) and others to a cultivated Rhododendron. Some of these 

 leaves are shown in a photograph reproduced in Fig. 179. 



As a result of the above recorded observations in Warwick- 

 shire, Surrey, and Cumberland, there can be but little doubt 

 that the phenomenon of bioluminescence in decaying leaves is of 

 common occurrence throughout the woods of England. 



As we have seen, luminous leaves have been found in France, 

 Germany, England, and Java. It seemed to me of interest to find 



