484 RESEARCHES ON FUNGI 



favouring the visibility of the spore-clouds, other than the high 

 temperature, were : the stillness of the air, the protection from wind 

 provided by the palings and the hedge, and the dark background 

 which happened to be available. 



Absence from King's Heath prevented my making any observa- 

 tions on the fruit-bodies during December 2-9. On visiting the tree 

 in the mornings of December 10-14, I was unable, using my naked 

 eye in diffuse daylight, to observe any spore-clouds passing away 

 from the fruit-bodies. This was doubtless due to low temperature 

 or too strong a wind, or to both conditions combined. 



December 15 was another warm and still day. On looking at 

 the fruit-bodies at 3.30 p.m. when the temperature of the garden 

 was 48° F., I again saw the largest one visibly shedding its spores. 

 Relatively dense spore-clouds were passing from beneath the gills 

 and becoming scattered by the wind (Fig. 200, A). 



On the night of December 15, and nightly until December 30, 1 

 examined the largest fruit-body for the emission of spore-clouds. The 

 electric hand-lamp, with which we have already become acquainted, 

 provided a source of light ; and, at the time of each observation, 

 the temperature of the air was taken by means of a thermometer 

 hung on a twig close by the fruit-body. On still cold nights, the 

 air under the trees by the fruit-body was found to be several degrees 

 warmer than that just above the grass of a near-by lawn. I hoped 

 that, for some of the observations, it would cool down to the freezing- 

 point of water, but its temperature was never once lower than 34° F. 

 At 11.45 P.M. on December 15, I went into the garden and, using 

 the hand-lamp for the first time, examined the fruit-body. The 

 weather was mild and the thermometer registered 43° F. Thick 

 clouds of spores could be seen coming from the pileus and being 

 borne away by the light airs of the night (c/. Fig. 200, D). 



From December 15 to December 29, during fifteen successive 

 nights, the fruit-body was found to be discharging spore-clouds. 

 The coldest night was December 27 when the thermometer registered 

 34° F. ; but, even at this temperature, the fruit-body continued to 

 emit spores, although but relatively few per minute (c/. Fig. 200, B). 

 On the night of December 29, which happened to be very mild, 

 I was able to demonstrate the discharge of spores to two friends. 



