PANUS STYPTICUS LUMINESCENS 407 



the intensity of the Ught was unchanged. This observation shows 

 that the maximum temperature for luminescence in Panus stypt. 

 luminescens is above 30° C. 



35° C. Some fruit-bodies, in the same manner as for the three 

 experiments just described, were exposed to a temperature of 35° C. 

 The hght from the gills began to grow dim after 6 minutes and was 

 relatively feeble after 12 minutes ; but, after an hour from the 

 beginning of the experiment, the fruit-bodies were still very faintly 

 luminous in spots. This experiment therefore indicates that in 

 Panus styptlcus the maximum temperature for luminescence is about 

 35° C. 



10° C. An experiment with a temperature of 10° C. was carried 

 out by placing cold water in the beaker and by adding colder water 

 when necessary. Fifteen minutes after exposure had begun, the 

 fruit-bodies were still glowing brightly and thereafter continued to 

 glow in an even manner without their photogen showing any trace 

 of injury from the reduced temperature. 



Summing up the results of the temperature experiments which 

 have now been recorded, we may conclude that : the maximum 

 temperature for the luminescence of Panus stypt. luminescens fruit- 

 bodies is 35° to 37° C, the minimum temperature — 2° to — 4° C, 

 and the optimum about 10° to 25° C. 



The following Table embodies the data for temperature as 

 obtained by Kawamura for Pleurotus japonicus and by mj'^self for 

 Panus stypt. luminescens. 



Bioluminescence and Temperature. 



From the data in the Table it is evident that the maximum 

 and minimum temperatures for the luminescence of Panus stypt. 

 luminescens are each several degrees lower than the maximum and 

 minimum temperatures respectively of Pleurotus japonicus. The 



