Penicillium Glaucum. 



ORIGIN. Widely distributed in the air, water and soil. 

 60 per cent, of the mould contaminations in the laboratory 

 are said to be due to this organism. 



COLOR. Is at first whitish, then becomes bluish-green. 



MYCELIUM. Consists of horizontally arranged, straight 

 or slightly wavy, jointed mycelial threads from which the 

 fruit hyphas rise vertically. 



FRUIT-ORGANS. The ends of the septate fruit hyphae are 

 forked, and are covered with the intermediate spore bear- 

 ers, or sterigmae, also sometimes called basidia. Each of 

 these in turn bears a row of 8 spores or conidia, so that 

 the appearance of the whole is that of a brush. The 

 spores are about 3.5 P. wide. 



GROWTH. Is rapid. 



Gelatin plates. The colonies form whitish floccules which rapidly 

 increase in size, and at the same time the center colors green. The 

 gelatin is liquefied quite early. A low objective will show the above 

 characteristics of growth. 



Bread flasks. Show a low, finely flocculent covering, which at 

 first is white but soon changes to a distinct green. 



TEMPERATURE. The optimum temperature is from 22 to 

 26. It does not grow at the temperature of the body. 



BEHAVIOR TO GELATIN. Slowly liquefies. 



PATHOGENESIS. It has no effect on animals. It fre- 

 quently develops on grapes and causes a marked alteration 

 in wine. It gives rise to inverting and to diastatic fer- 

 ments. This organism is said to be used in the preparation 



of Roquefort cheese. 



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