23 OERSTED, ON THE AGARICINI. 



It was only by preparations made in this way that I suc- 

 ceeded in getting a clear view of the mycelium-filanaents, and 

 of the organs seated thereon, of which I had previously only 

 got an indistinct glimpse, as well as arriving at a knowledge 

 of the organs of fertilisation so long in vain sought after in 

 these fungi. 



3. 



The mycelium consists of very long, tubular, and branched 

 cells, -jl-^ = —Iro mm. in diameter, and loosely felted amongst 

 one another. These cells are very regularly dichotomously 

 branched, which is especially distinctly seen when the 

 mycelium is formed, as above mentioned, upon little glass 

 plates, as the mycelium then forms only a single layer. 



The principal stem divides into two branches ; these divide 

 again in the same manner ; and this branching is repeated to 

 the extreme points. The cell-membrane is extraordinarily 

 thin and soft and mucous — it has almost the character of a 

 mucous membrane — so that the cell-filaments readily become 

 confluent, a condition which has a peculiar interest in that it 

 shows the relationship of these mycelium filaments with the 

 Plasmodium of the Myxogastres (Slimsvampe) ;* the cell-con- 

 tents, when slightly magnified, appear as a light-yellow 

 mucus ; but with a higher magnifying power they are seen to 

 be almost exclusively formed of greyish, partly very minute, 

 partly larger granules, amongst which occur minute yellow 

 globules (oil-drops ?.) ; the larger granules are often sur- 

 rounded by a clear mucous investment, and sometimes there 

 occur large, almost clear, slightly reddish, mucous masses. 



Of the organs which present themselves upon the myce- 

 lium, should be first mentioned the bud-cells (Knopceller), or 

 the above mentioned three-celled filaments, with a globular 

 cell at the apex. These now present themselves under so 

 different an appearance, that one cannot readily believe them 

 to be the same organs which were previously before one. 

 The septa have quite disappeared from the stems, and, 

 instead of the globular cell, have come a considerable number 

 of verv minute cells. That the above described form, that 

 under which these organs present themselves when seen in air, 

 depends upon an optical illusion produced by the draAving 

 together of the cell-contents and cell-membrane, we can 

 readily satisfy ourselves by observing the gradual transforma- 



* Compare, thus, the mucous net formed by tlie uuion of the mycelium 

 filaments (tab. i, fig. 10) with the plasmodinm o{ Didj/mium leucopns (Prings- 

 heim's ' Jabrbiicher fiir wissench. Botanik,' 3 Bd., 1SG3, tab. xviii, fig. 7). 



