Mucor Rhizopodiformis, Lichtheim. 



Origin.— White bread kept at 37°. 



Color. — At first white, but later becomes .grayish. 



Mycelium. — The mycelial threads are colorless, later on 

 brownish, and thicker than those of the preceding mucor. 

 They are not jointed or divided. At first the growth is 

 white, then becomes grayish. 



Fruit-organs. — The fruit hyphae occur in groups or 

 bunches, which adhere to the nutrient medium by means of 

 special root tufts. The large dark sporangia on the ends 

 of the hyphae contain colorless rounded spores which are 

 larger than those of the preceding organism (5-6 /j-). 



Growth. — Is rapid and has a pleasant odor. 



Qelatin plates. — Development is best wlien the gelatin is made 

 ■with, bread infusion. It forms a coarse grayish-black mass which 

 liquefies the gelatin. 



Bread flasks. —The growth is lower than that of M. corymbif er, 

 and is grayish, owing to the dark colored sporangia. An ethereal or 

 aromatic odor is present. ' 



Temperature. ^Slow growth at 12 to 15°; develops best 

 at 37°. ^ 



Behavior to gelatin. — Liquefies. 



Pathogenesis. — ^It has a similar effect as M. corymbif er, 

 but is more pathogenic. i 



The mucors are characterized by marked fermentative 

 powers. They convert dextrose and maltose into alcohol. 

 Only one species, however, can invert cane-sugar. Some 

 species may produce 7-8 per cent, of alcohol and many of 

 them give rise to diastatic ferments. The most common 

 species is the M. mucedo which is relatively frequent on the 

 excreta of herbivorous animals. The M. racemosus is like- 

 wise common and its spores are found in the air. 



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