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The vinegar plant was naturally vegetative only ; year after year cells were 

 added to cells, and filaments to filaments, but there was nothing to be 

 found about it of the character of a seed. So long as sweet water was 

 supplied to it, so long it kept growing in this manner ; but if a check took 

 place and it could no longer get what it wanted to feed upon, directly it 

 began to starve, it shot up a number of filaments, and it became covered 

 with a beautiful crop of blue mould. When these filaments were developed 

 to their full extent, a number of chains of bead -like spores appeared at the 

 top, hence this mould was called Penicillium. No end of these were pro- 

 duced, and when the spores ripened and dropped off, every one was capable 

 of producing a plant. Each chain, it would be observed, proceeded from 

 a small branch, each of them growing in pairs, the top of the thread 

 forked out into some elongated cells, and on these grew the chain of spores. 

 If any member of the Club, who was desirous of studying these things, 

 did not happen to possess a vinegar plant or a piece of mouldy bread, if 

 he were to take up a small portion of fresh horse-dung and put it under a 

 bell glass, in 48 hours he would have a strong supply of this mould. If 

 they shook off some of these spores into a hollow glass slide containing 

 a little sugar and water, they would in the course of a few hours be 

 able to detect each one sending out a short filament, and branching out 

 in various directions. Each spore would measure, say the 5 f )i7 of a 

 millimetre or "005 of an inch, and each one was perfectly capable of 

 producing a vinegar plant. Another mould, nearly of the same size, and 

 resembling it to the naked eye, was found in similar places. The top of the 

 stem is swollen and simple, the chains of spores are seated on elongated 

 cells, which spring from the thickened apices of the threads. This is 

 the Aspergillus glaucus. Another remarkable thing might be observed 

 in this mould — when it grows on some substances, under favourable con- 

 ditions, the mycelium at the base curled up at the ends in a curious 

 way, twisting itself round like a corkscrew, until at length it became 

 quite like a ball. It then became absorbed into a globose form, clear 

 and colourless, and containing a number of globules. Gradually the 

 outside wall thickened, it became of a yellow colour, and it was transformed 

 into a fungus of a different character, belonging to a different group, 

 and as widely distinct from its original type as a blade of grass was 

 from a walnut tree. The structure of these globose bodies was an out- 

 side reticulated wall containing cells called asci, these again containing 

 eight small bodies called sporidia ; when the outside case broke, the ascus 

 opened by a small lid, and the spores escaped, and each one of these 

 was capable of producing not always something like itself, but either of 

 the other species. This fungus was known as Eurotium herbariorum, 

 and upon old specimens of dried flowers or insects they would often find 

 these little golden balls, which were only another phase of the growth 

 of a very common mould. 



The Chairman said that it had passed into a proverb that it was difficult 

 to speak gracefully upon common things, but this task their friend, 

 Dr. Cooke, had succesfully accomplished. He should be glad to hear 



