ON CYSTIDIA. 183 



entirely gratuitous opinion had foundation we should here have 

 less to do with a real fecundation than with a phenomenon of 

 nutrition. As far as I know, there exists no other observation on 

 any female organ susceptible of fecundation by the cystidia, and the 

 known facts fully authorize us only to see in them pilose produc- 

 tions of a particular order. Many cystidia have, in fact, just the 

 form of ordinary cylindrical hairs, those of the Coprini have the 

 greatest resemblance to the hairs spread over the sterile surface of 

 the cap, and in many fungi we find positive pilose formations in 

 the place where in others the cystidia are placed ; it is sufficient to 

 quote the edges of the tubes of Fistulina, and the setiform appen- 

 dages which are prominent on the hymenial surface of several 

 Thehphorce, such as Corticium quercinum and especially Tlielephora 

 (Hymenochcete) tabacina, and other species of the group which 

 constitute M. Leveille's Hymenochcete ;* these appendages resemble, 

 it is true, pollenidia, but their sides are everywhere hard and 

 thick. 



Quite recently M. A. S. CErsted has discovered a trace of sexual 

 organs in the Hymenomycetes where, perhaps, no one had pre- 

 viously looked for them.-(- He has seen, in fact, in Agaricus 

 variabilis, Pers., oocysts or elongated reniform cells, which sprung 

 up like rudimentary branches of the filaments of the mycelium, and 

 enclose an abundant protoplasm, if not even a nucleus. At the 

 base of these oocysts appear the presumed antheridia, that is to say 

 one or two slender filaments which generally turn their extremities 

 towards the oocysts, and which more rarely are applied to them. 

 Then, without ulteriorly undergoing any appreciable modification, 

 the fertile cell or oocyst becomes enveloped in a lacework of fila- 

 ments of mycelium which proceed from that which bears it, and 

 this tissue forms the rudiments of the cap. The reality of some 

 kind of fecundation in this circumstance, and the mode of the phe- 

 nomenon, if there is one, are at present equally uncertain. If M. 

 (Ersted's opinion is confirmed, naturally the whole of the cap will 

 be the product of fecundation. As long ago as 1860 M. Karsten 

 presumed that such was the case. His observations on the first 

 development of Agaricus cajnpestris , as far as we can judge by the 

 rather obscure account given in " Bonplandia" (1862, pp. 63), 

 would agree with M. CErsted. It is impossible not to perceive the 

 similitude between the phenomena seen by M. CErsted and those I 

 have described in Peziza confluens. 



* See Annates des Sciences Naturelles, 3rd series, vol. v. (1846), p. 150. 

 t See Verhandl : der Konig : Dan : gesell : der Wiss : 1st January, 18G5. 



