YEASTS AND MOLDS 2OQ 



True Molds. Fliigge has made five distinct divisions of 

 molds. It will, however, serve our purpose to classify those 

 to be described under three headings : Penicillium, Mucor, and 

 As per gill us. 



Penicillium Glaucum. Origin. The most widely dis- 

 tributed of all molds, found wherever molds can exist. 



Form. From the mycelium, hyphae spring which divide into 

 basidia (branches) , from which tiny filaments arise (sterigmata) , 

 arranged like a brush or tuft. On each sterigma a little bead 



Fig. 125. Penicillium glaucum (x 500) (Frankel and Pfeiffer). 



or conidium forms, which is the spore. In this particular fun- 

 gus the spores in mass appear green. 



Growth. It develops only at ordinary temperatures, forming 

 thick, grayish-green molds on bread-mash. At first these 

 appear white, but as soon as the spores form, the green pre- 

 dominates. Gelatin is liquefied by it. 



Mucor Mucedo. Next to the Penicillium glaucum, this is 

 the most common mold. Found in horse-dung, in nuts and 

 apples, in bread and potatoes, as a white mold. 



Form. The mycelium sends out several branches, on one of 

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