198 



ItOYAL UOltTICULTUliAL SOClETr, 



The snow-white mycelium runs for three or four inches over 

 the leaf (on the under side of the specimen before me), consisting 

 of fine branched threads composed of numerous filaments loosely 

 intertwined, and studded everywhere with little balls, which make 

 it an extremely pretty object. 



The threads are slightly flexuous, with rather long articulations, 

 and short obtuse branches, some of which probably are elongated 

 as the spawn advances, though I have not been able to trace the 

 origin of the threads. Upon the threads are scattered linear 

 bodies disposed obliquely and generally changing their direction 

 alternately, and a few are scattered amongst the threads. These 

 appear to be conidia; but I have not seen them growing on 

 the filaments. At first sight they seemed to be internal ; but a 

 nice adjustment showed them projecting beyond the threads on 

 which they were seated. Occasionally a single thread is found 

 with projecting knots on the sides, divided halfway down, as in the 

 genus Zygodesmus, but whether accidentally present or not I am 

 unable to determine. Short fascicles of inarticulate filaments oc- 

 casionally appear, with their endochrome collected in distinct 

 masses, which are probably the first rudiments of the little balls 

 above mentioned. These are seated on the little creeping ropes, and 

 under a good lens are rough everywhere with projecting processes 

 so as to form a pretty microscopic object. On dissection, the balls 

 are found to consist, below, of interlaced, repeatedly branched, 

 rather irregular filaments, giving off", either at their sides or extre- 

 mities, a short necklace consisting of from three to five joints, 

 w r hich are all more or less swollen, the terminal one being fre- 

 qently rather obtusely apiculate. It is these terminal joints 

 radiating in every direction which give the balls the rough appear- 

 ance mentioned above. The basal joints are filled with a granular 

 endochrome, the granules vanishing as the terminal joints are 

 formed. 



Unfortunately the full development of this destructive fungus 

 lias not yet been observed, which is no doubt capable of propagation, 

 either from the oblong bodies or the deciduous joints of the balls. 

 It is very probable that it is the spawn of some Agaric, which has 

 spread from the Sphagnum about the roots of the Orchids to the 

 leaves. I have seen an undescribed Agaric of the subgenus Omplialia 

 on Sphagnum at Mr. Eucker's, and I am inclined to think that it 

 is to this the mycelium belongs, but I have no proof to give that 

 such is the case. It is undoubtedly of some importance to ascer- 



