PANAEOLUS CAMPANULATUS 



319 



Abnormalities in the basidia of Coprinus niveus include not 

 only tristerigmatic and pentasterigmatic basidia, but also spores 

 which exhibit equal or unequal bifurcation to a greater or less 

 degree. Some of these curious spores are illustrated in Fig. 110. ' 



Hexasterigmatic 

 basidia occur in Sisto- 

 trema confluens Fr., 1 

 Cantharellus cibarius, 

 and some other species 

 of Cantharellus. 2 

 Basidia with six 

 sterigmata are also 

 not infrequent in 

 Exobasidium vaccinii 3 

 and some species of 

 Corticium. 4 The bases 

 of the sterigmata for 

 each basidium have 

 the same relative posi- 

 tions as the corners of 

 a regular hexagon. 



Heptasterigmatic 

 basidia, so far as I FlG - 109 - c P rinus rcoticus. Photograph of the 



hymenium, to show that the basidia are tri- 

 sporous. The basidia, as in most Coprini, are 

 dimorphic. The spores of most of the long 

 ones only are in focus, and the spores of the 

 short ones out of focus. There are three spores 

 only above each basidium. In the middle of 

 the right-hand side the spores were removed 

 from their sterigmata during the making of the 

 preparation. Magnification, 440. 



know, are not the rule 



in any of the species 



of Hymenomycetes. 



However, they occur 



exceptionally in some 



Thelephoraceae where 



the normal number of sterigmata is eight. I have not seen any 



such basidia myself but, doubtless, where they occur, the relative 



positions of the sterigmata are like those of the corners of a regular 



heptagon. 



1 N. PatouiUard, loc. cit., p. 111. 2 Cf. V. Fayod, loc. cit., p. 262. 



3 N. Patouillard, Essai taxonomique sur les families et les genres des Hymeno- 

 mycetes, Lons-le-Saunier, 1900, p. 35. 



4 F. von Hohnel und V. Litschauer, loc. cit., p. 84. 



