PSALLIOTA CAMPESTRIS 445 



general level of the hymenium /. In the unclear spot, u, no 



FIG. 151. Psalliota campestris (wild form). Camera-lucida drawings of an old, 

 nearly exhausted hymenium showing past-generations basidia arising at 

 various levels of the subhymenium. A and B are cross-sections. In A, the 

 elements nos. 1, 2, and 3 are present-generation basidia from which the spores 

 were knocked off in cutting the section as at 3 ; but in 1 and 2 the spores have 

 been restored semi-diagrammatically ; no. 4, an old past-generation basidium 

 arising from the subhymenial cell no. VIII ; nos. 5, 6, and 7 are paraphyses ; 

 I, the general level of the hymenium including tops of no longer distinct past- 

 generations basidia ; w, waste spores lying on the hymenium ; the subhymenium 

 consists roughly of three layers of cells : I, II, III, and IV ; V, VI, and VII ; 

 VIII, IX, and X. In B, nos. 1 and 2 are present-generation basidia from 

 which the spores were knocked off, but for no. 2 the spores have been restored 

 semi-diagrammatically ; nos. 3 and 4, coming-generation basidia ; nos. 5, 6, 

 7, 8, and 9, past-generations basidia ; nos. 5 and 7, the longest and oldest, 

 arise from near the base of the subhymenium ; nos. 9, 6, and 8 arise 

 successively at higher levels, while the basidium no. 4 arises at a still higher 

 level ; u, unclear spot where outlines of the cells could not be distinguished ; I, 

 general level of the hymenium made of indistinct tops of past-generations 

 basidia ; there are roughly four layers of subhymenial cells : I, II ; III, IV, 

 V, VI, VII ; VIII, IX, X ; XI, XII, XIII ; basidia arise at all these levels. 

 C, a surface view of the hymenium of the same material, showing such elements 

 as could be clearly distinguished ; a, past-generation basidia (as seen in water, 

 brownish and with no distinguishable sterigmatic stumps) ; b, a coming- 

 generation basidium ; c c, small paraphyses. Magnification, 1,040. 



individual element can be made out. The absence of any level 

 plane sharply separating the hymenium from the subhymenium is 



