i8 RESEARCHES ON FUNGI 



lucida drawing in Fig. 7 at A (p. 14) shows that the spores of basidia 

 belonging to an older generation frequently stand in part vertically 

 above the spores of a younger generation. 



Correlation of Facts. — We are now in a position to correlate all 

 the different facts connected with the organisation of the hymenium. 

 The fruit-body of Lepiota cepaestipes is adapted to shed its spores 

 in little more than 12 hours, and with this brief spore-discharge 

 period is correlated its ephemeral existence. On account of its 

 being ephemeral, it does not need to be as rigid as equally large 

 fruit-bodies belonging to other species which must persist for many 

 days before all their spores are shed. Hence the pileus is provided 

 with little flesh, and this has a very loose texture. For the same 

 reason, the trama of the gills is also extremely light in construction. 

 The fruit-bodies expand their pilei in the evening and shed their 

 spores at night and in the early morning. At night there is no hot 

 sun to be encountered and the air is much more saturated with 

 moisture than in the day, so that the fruit-bodies open when there 

 is least danger of too rapid transpiration. This periodicity of 

 development, which corresponds with that of several small and 

 delicate species of Coprinus, e.g. C. ephemerus, seems, therefore, 

 to have a biological significance : it protects the lightly constructed 

 fruit-bodies from transpiration dangers. Now, granted that the 

 spores are to be discharged in a little over twelve hours, it is fitting 

 that the development of the different generations of basidia should 

 take place in a manner differing from that with which we became 

 acquainted in our studies of the Panaeolus Sub-type. Instead of 

 there being a large number of generations (eight to twelve), the 

 generations have been reduced to four only. Not only this, but the 

 development of successive generations has been hastened. Instead 

 of a succeeding generation of basidia waiting until the discharge of 

 the spores of the preceding generation has been accomplished before 

 producing its own spores, as happens in fungi of the Panaeolus 

 Sub-type, we find in our Lepiota that, shortly after the first-genera- 

 tion basidia have begun to develop spores, the second-generation 

 basidia begin to develop spores also. Indeed, all the four genera- 

 tions of basidia in our Lepiota may be developing and maturing 

 spores at one and the same time, although the first-generation 



