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threads which spread through the fluid, or creep on the surface of 

 the substratum on which it grows, it soon sends up erect stalks 

 which branch at tlieir summit, and produce there a mass ot 

 very minute pale blue spores ; these soon ripen, and drop 

 off and are carried far and wide by the aii- to infect other 

 substances, so that no place is free from them. Brefeld terms 

 Penicillium glaucum '•' the lord and ruler among its brethren," 

 and says, when we speak of mouldiness it is of this species that 

 it is said par excellence. I have often experienced the vegetative 

 power of this Mould to my annoyance when endeavouring to grow 

 rare species of Moulds on boiled rice or paste. Before the plant 

 in cultivation has had time to establish itself Penicillium glaucum 

 has made its appearance, and so quickly has it taken possession 

 of the paste that the desired species has been completely stifled 

 and destroyed. 



Although Brefeld fjxiled to make yeast-globules produce the 

 Penicillium by cultivation, he is nevertheless of opinion that 

 certain moulds (mucorinei) do produce fermentation in saccharine 

 solutions ; he states that the presence of sugar is necessary to 

 their thus operating. 



For this reason barley is made to undergo the process of 

 malting, which consists in causing the grain to germinate by the 

 application of heat and moisture : in germinating, the starch con- 

 tained in the corn is converted into sugar to serve in the natural 

 course as food for the young plant ; at this stage germination is 

 checked, and the sugar is thus preserved. When placed in sweet- 

 wort the yeast-globules, or the mycelia of moulds, have the 

 property of decomposing the sugar and converting it into carbonic 



from veins immediately into glass vessels does not putrefy when proper precau- 

 tions have been taken to exclude extraneous spores, or germs ; but if a morsel 

 of putrefied blood were applied to it the putrefaction would speedily spread 

 through the whole mass." Further on he intimates that moulds, such as 

 Torula, &c., are the cause of the fermentation alluded to. It takes possession 

 of the ink we write with, and even of poisonous solutions, as sulphuric acid. 



