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BACTERIOLOGICAL METHODS 



organisms. Cheese poisoning is not uncommon, due to the pres- 

 ence of bacteria which give rise to toxins (tyro-toxicon) . In a 

 general way it may be stated that cheese diseases are due to 

 filthy and unsanitary conditions in the dairying establishment re- 



FiG. 46. — Penicillium glauciim showing the characteristic spore formation. This 

 fungus is a true saprophyte, the common green mold, occurring on a great variety 

 of organic substances. 



suiting in infected milk, or to filthy and unsanitary conditions in 

 the cheese factory, or the infection may be traceable to the im- 

 proper and careless storing and handhng of the cheese. Ripened 

 cheese being in itself a decomposition product resulting from the 

 invasion of certain desirable micro-organisms usually entering 



