40 DUBLIN NATUHAL HI8T0ET SOCIETY. 



they dried up, and, becoming withered, my hopes of having flowers were 

 thus ended. On examining the roots of the plants, I found them 

 to be diseased ; they had a very offensive odour, had assumed a pale- 

 brown colour, and those which were farthest advanced in decay con- 

 tained numerous bubbles of fetid gas, which I may state was not sul- 

 phuretted hydrogen. The decay appeared to me usually to commence 

 from below, and to spread upwards in the roots, the epidermis still re- 

 maining firm after the interior was decayed. The microscope showed that 

 the cells of the plant were separated from each other by lines of small 

 dark dots which formed continuous chains ; when these dots first ap- 

 peared, the cells were healthy-looking, then became darker coloured, 

 their contents broken up, and finally the cells themselves seemed to be- 

 come isolated and detached, and to soften down. 



Placed in fluid and carefully watched, I saw a small tuft of vegetation 

 gradually arise from the side of some of the root, and after a few days 

 its fibres crept beyond the fiuid and developed into an Aspergillus (pro- 

 bably A. candidus). I may state that, on examining them, I found 

 moulds developed on the hyacinth bulbs ; I believe it is very common 

 for them to be injured from this cause, the mould acting as a canker, 

 and the part requiring removal with a knife. I had purposed repeat- 

 ing my investigations this spring, but was unable to do so from other 

 occupations. I would, in conclusion, merely remind you that this plant, 

 or its close relative {A. glaucus), is the mould the presence of which 

 is so highly prized in cheese that it is, I believe, often inoculated with 

 it to produce an article fit for the epicure. 



A series of microscopic drawings illustrated these remarks. 



The President remarked that many other fungi, during the progress 

 of their development, take on most dissimilar forms. Old botanists, 

 hence, have often referred to distinct genera forms which have now 

 been proved to be specifically identical. One genus, for instance, Sclero- 

 tium, of which some twenty or thirty species have been described, is 

 found to be really made up of the young states of the genera Agaricus 

 and Pezziza, so that Sclerotium is now nearly blotted out from our lists. 

 Among the drawings exhibited to-night we see that a plant which we 

 would be led to call Lcptomitus, when traced to its full development, 

 turns out to be Aspergillus. When in North America he was shown a 

 number of so-called species of this false genus, at that time placed 

 among the sea-weeds, which had developed themselves among the sul- 

 phate of copper solutions used in the electrotyping processes of the United 

 States Survey. The plant had caused much annoyance and damage 

 to the service, decomposing the solution, and throwing down the cop- 

 per to such an extent as to render it nearly impossible to carry on the 

 various processes required. He hoped Dr. Frazer would follow up this 

 subject; the Irish fungi were nearly unknown, and a fine field was 

 open for any one who would pursue the subject of the metamorphoses 

 of these interesting plants. 



