LEPIOTA PROCERA 23 



A precocious excretion of a very large drop of water from the 

 hilum of a young spore was described in Volume II. ^ 



Remarks on Lepiota procera. — It may be asked : is the organis- 

 ation of the hymenium of Lepiota cepaestipes, with which we have 

 just become acquainted, common to all species of Lepiota i The 

 answer is : no. However, the only other Lepiota which I have 

 examined for hymenial organisation is L. procera. 



The magnificent fruit-bodies of Lepiota procera, the Parasol 

 Fungus (Figs. 14 and 15 ; also Vol. I, Figs. 14 and 15, pp. 44 and 45), 

 as every mycologist knows, stand upright for several days after 

 their pilei have opened out. After some too limited observations 

 of my own had revealed that the spore-discharge period of this 

 species is at least three days in length, Mr. Sidney Dickinson, at 

 my request, determined the full length of the spore-discharge 

 period of a fruit-body growing in the open in Kew Gardens. The 

 following is a summary of Mr. Dickinson's field-notes.'^ A very 

 young fruit-body of Lepiota procera was first seen coming up on 

 September 9, 1922. On September 10, 11, and 12, its pileus was 

 found to be increasing in size. On September 13, the pileus was 

 expanding and the velmti partiale had become broken leaving an 

 annulus around the stipe. A glass slide was then placed under the 

 gills. At 10 A.M. the next morning, September 14, spores were 

 found deposited on the slide. Thereupon a new slide was placed 

 under the gills ; and, thereafter, this replacement was repeated 

 daily until the spore-discharge period had come to an end. Spore- 

 deposits were found upon the slides each morning from September 14 

 to September 21 inclusive. It was thus proved that the spore- 

 discharge period of the fruit-body was of eight days' duration. 



As we have just seen, the fruit-body of Lepiota procera, after 

 the expansion of the pileus, remains standing and continues to 

 shed spores for some eight successive days. It is therefore per- 

 sistent, and not ephemeral like that of L. cepaestipes. This dif- 

 ference between the two species in persistence is correlated, as we 

 might expect, with a difference in hymenial structure. 



1 These Researches, vol. ii, 1922, pp. 17-18, Fig. 9. 



2 In lilt. I here desire to express my thanks to Mr. Dickinson for making the 

 observations and sending me his record of them. 



