THE BOLBITIUS SUB-TYPE 6i 



chief difference in the fruit-body mechanism of the ephemeral fruit- 

 bodies of the Bolbitius and Psathyrella Sub-types is to be found in 

 the organisation of the hymenium. 



We shall now consider in detail the special characters of the 

 Bolbitius Sub-type. These are as follows : 



(1) The whole structure of the fruit-body is relatively light and 

 suited to a brief duration of the pileus. 



(2) The spore-discharge period is very brief ; but, unfortunately, 

 up to the present, I have not found an opportunity to measure it 

 exactly. However, I have frequently noticed that fruit-bodies 

 which expand one day die down the next. Moreover, the ephemeral 

 nature of the fruit-bodies of the Bolbitii has been remarked upon by 

 numerous authors, several of whom have lil^ened the genus Bolbitius 

 to Coprinus. We are therefore justified in assuming that the length 

 of the spore-discharge period in the Bolbitius Sub-type is about 

 24 hours. 



(3) The gills are not mottled, and there are no waves of develop- 

 ment passing over the hymenial surface ; the hymenium develops 

 everywhere in a very even manner. In this respect we have a 

 distinct contrast with the Panaeolus Sub-type. 



(4) As a rule, it is impossible to determine the number of genera- 

 tions of basidia which come up on a small area of the hymenium 

 during the spore-discharge period, owing to the fact that, on such 

 a small area, at any one time, one can observe basidia in all stages 

 of development unassorted into groups of any kind. But sometimes 

 it happens that, on a small area, the basidia and paraphyses take on 

 a remarkably regular pattern and the basidia develop in successive 

 groups. One can then observe that the number of generations of 

 basidia which develop is four. This is a great reduction on the 

 number of successive generations which are found in the Panaeolus 

 Sub-type, but is equal to the number in the Psathyrella Sub-type. 



(5) Adjacent basidia do not develop spores simultaneously. 

 Basidia with spores of about the same age are a little distance apart. 

 Younger basidia, which begin to develop spores between older ones 

 bearing spores, are usually situated in the middle of the spaces 

 between the older basidia, so that younger basidia do not interfere 

 mechanically with older ones. 



