Prof. H. Karsten on the Fecundation of the Fungi. 75 



over the central ovicell, which in the meantime increases in 

 size*. 



A similar organ, according to Bary, was lately found by 

 Oerstedt on the mycelium of another species of this genus, 

 namely, A. variabilis. This accomplished observer also mentions 

 elongate, reniform, pedunculated cells, containing albuminoid 

 plasma and apparently a nucleus. Near these cells, regarded 

 as equivalent to the female organs, Oerstedt found filamentous 

 organs, the ends of which were generally turned away from these 

 cells, and rarely bent towards them : these appeared to Oerstedt 

 to have possibly the function of anthers. Without any further 

 perceptible changes, the ovicell is afterwards enveloped by a web 

 of mycelium-filaments, which spring from the branch bearing it; 

 by this means the foundation of the cap is laid. 



This result harmonizes to a certain extent with my above- 

 mentioned view attained by the observation of the development 

 of the fruit of Cmnogonium, and corresponds both with my 

 above-detailed observations on A. campestris and with those 

 which I have since had the opportunity of making upon A. vagi- 

 natus, Bull. The latter, indeed, only enable us to advance one 

 step in the elucidation of this difficult subject; but as we are so 

 completely unacquainted with the first stages of development of 

 the fruit of Fungi, they may nevertheless fitly be communicated 

 here, in order to incite to a further investigation of the subject. 



For the repetition of these observations I selected A.vaginatus, 

 because, from its smooth mycelium-filaments, it seemed to me 

 to be better suited to the purpose than A. campestris. 



By going back from the developed fruits to younger states, 

 on the mycelium of this Agaric also I found, as the first indica- 

 tion and commencement of the pileus, simple cells of oblong 

 form, at first with short but afterwards with longer foot- stalks, 

 from two to five times the breadth of the filaments of the my- 

 celium. These had turbid albuminous contents (not shining, 

 as in ^. campestris); and in their centre a nuclear cell, filled with 

 rather clearer fluid, could be recognized. The pedicels were se- 

 parated by a septum both from the dilated terminal cell and 

 from the filament of the mycelium. Once I found two such 

 cells close together, both, however, with rather short pedicels, 

 and without any other branches in their vicinity (fig. 1). That 

 these bodies are not parasitic structures, but organs of the 

 fungus itself, is shown by the continuity of these branches, and 

 their perfect similarity in structure with those of the mycelium- 

 filament, beset with the commencements of fruit in their imme- 

 diate vicinity, from which they originated ; that they cannot be 



* Gesamraelte Beitrage, p. 344. 



6^ 



